Look back at parts A and B to compare the properties of the unknown elements with the properties of the known
elements. Based on these properties, match each unknown element to its group in the periodic table.
Drag each tile to the correct box.
Tiles
element 1 element 2
Pairs
group 1
group 2
group 11
group 14
group 17
group 18
element 3
element 4
element 5
element 6
Answers
Based on the properties of elements, elements can be arranged into groups in the periodic table as follows:
Group 1 to 3 - metals
Group 14 - non-metals, metalloids, and metals
Group 15 to 18 - non-metals
What are groups and periods in the periodic table?Groups are the names given to the periodic table's columns. In the table, individuals who belong to the same group make bonds of the same kind and have an equal number of electrons in their atoms' outermost shells.
Periods are the horizontal rows found in the periodic table.
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Related Questions
6. Calculate the pH of a buffer prepared by mixing 0.10 mol-L-' acetic acid (CH;COOH, HAc) and
0.10 mol L NaOH solution with the volume ratio of 3:1. (Answer pH = 4.45
Answers
CH3COOH + NaOH → CH3COONa + H2O
The resulting solution will contain both the weak acid (HAc) and its conjugate base (Ac-). The pH of the buffer can be calculated using the Henderson-Hasselbalch equation:
pH = pKa + log([Ac-]/[HAc])
where pKa is the dissociation constant of HAc, [Ac-] is the concentration of the acetate ion, and [HAc] is the concentration of acetic acid.
The pKa of acetic acid is 4.76.
To calculate the concentrations of HAc and Ac-, we can use the volume ratio of 3:1 to find the total volume of the solution:
Total volume = 0.10 L HAc + 0.03 L NaOH = 0.13 L
The concentration of HAc is:
[HAc] = 0.10 mol / 0.13 L = 0.769 mol/L
The concentration of Ac- is:
[Ac-] = 0.03 mol / 0.13 L = 0.231 mol/L
Now we can substitute these values into the Henderson-Hasselbalch equation:
pH = 4.76 + log([0.231]/[0.769]) = 4.45
Therefore, the pH of the buffer is 4.45.
pH = pKa + log([A-]/[HA])
where [A-]/[HA] is the ratio of the concentration of the conjugate base to the concentration of the weak acid. In this case, acetic acid is the weak acid and its conjugate base is acetate (CH3COO-).
The volume ratio of the acetic acid and NaOH solutions is 3:1. Therefore, we can assume that we have 0.075 L of acetic acid solution and 0.025 L of NaOH solution.
The concentration of acetic acid is 0.10 mol-L¹. Therefore, the number of moles of acetic acid is:
moles of HAc = concentration × volume = 0.10 mol-L¹ × 0.075 L = 0.0075 mol
Since the volume of the NaOH solution is 0.025 L and its concentration is 0.10 mol-L¹, the number of moles of NaOH is:
moles of NaOH = concentration × volume = 0.10 mol-L¹ × 0.025 L = 0.0025 mol
The NaOH reacts with the HAc to form water and acetate:
NaOH + HAc → NaAc + H2O
Since the number of moles of NaOH is less than the number of moles of HAc, all of the NaOH will react with the HAc. Therefore, the number of moles of acetate formed is:
moles of acetate = moles of NaOH = 0.0025 mol
The number of moles of HAc remaining after the reaction is:
moles of HAc remaining = moles of HAc - moles of acetate = 0.0075 mol - 0.0025 mol = 0.0050 mol
The total volume of the buffer is 0.075 L + 0.025 L = 0.1 L. Therefore, the concentration of acetate is:
concentration of acetate = moles of acetate / volume of buffer = 0.0025 mol / 0.1 L = 0.025 mol-L¹
The concentration of HAc is:
concentration of HAc = moles of HAc remaining / volume of
The student who represents Earth sees different stars from different positions in the circle. How does this model suggest evidence that Earth circles the sun once a year?
Answers
Earth orbits the sun in a predictable pattern. The pattern of Earth's seasons depend on how much sunlight reaches different areas of Earth as the planet moves around around the sun. It is the earth sun model which shows that the earth circles the sun once a year. So revolution is responsible for it.
Earth has a nearly circular orbit around the sun, Earth also rotates around its north-south axis, an imaginary line passing through earth from pole to pole. Every place on the planet gets 12 hours of light and 12 hours of dark each day.
The temperature conditions on the planet change depending on the distance from the sun. There are colder temperatures at the poles and warmer temperature at the equator.
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How many moles of oxygen are in 2.71 x 1025 molecules of carbon dioxide (CO2)?
Answers
Answer:
There are 4.52 moles of oxygen in 2.71 x 10^25 molecules of carbon dioxide (CO2).
Explanation:
Which type of symbiotic relationship best describes the relationship between cotton plants and wasps?
a: parasitic - the cotton plants are helped, but the wasps are harmed
b: commensal - the cotton plants are helped and the wasps are unaffected
c:mutualistic - both the cotton plants and the wasps are helped
Answers
Answer:
The answer is c. ( mutualistic ).
Explanation:
The relationship between cotton plants and wasps is an example of mutualism. The cotton plants provide a food source in the form of nectar for the wasps, and in return, the wasps serve as pollinators for the cotton plants, which helps the plants reproduce. This is a mutually beneficial relationship, as both species benefit from the interaction. Therefore, the answer is (c) mutualistic.
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What happens to a buffered solution
when a small amount of base is
added?
Answers
Answer: When you add small quantities of an acid or alkali (base) to it, its pH does not change significantly. In other words, the buffer solution stops the acid and base from neutralizing each other.
Answer:
the result is a decrease in the amount of conjugate base present and an increase in the amount of the weak acid.
Explanation:
what is the answer to this question and how do i figure it out?
Answers
The m/z that can be seen in propan - 1 ol but not propan - 2 ol is m/z = 15
What is the mass spectrum?The distribution of ions produced by a sample in a mass spectrometer is depicted graphically as the mass spectrum. A sample is ionized in a mass spectrometer, where the resultant ions are sorted according to their m/z ratio.
Each peak in the mass spectrum corresponds to a certain m/z ratio and represents one of the several ions that the sample produced. Thus the propan - 1 ol has the m/z = 15
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Calculate volume of 0.3 mole of hydrogen chloride
Answers
6.72L is the volume occupied by 0.3 mole of hydrogen chloride. A measurement of three-dimensional space is volume.
A measurement of three-dimensional space is volume. It is frequently expressed quantitatively using SI-derived units, like the cubic foot and litre, or different imperial or US-standard units, including the gallon, quart and cubic inch. Volume and length (cubed) have a symbiotic relationship. A container's capacity is typically thought of as being represented by its volume.
Volume = 0.3×22.4
=6.72L
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Given the reaction:
If there are initially 14.2 moles of iron (III) nitrate nonahydrate, how many moles of steam (water vapor) will be produced?
Answer in mol.
Answers
Total, 127.8 moles of the steam (water vapor) will be produced.
Iron(III) nitrate nonahydrate, or Fe(NO₃)₃·9H₂O, is a compound that contains iron (III) cations (Fe³⁺) and nitrate anions (NO₃⁻) combined with nine water molecules (H₂O) per formula unit. The nine water molecules are referred to as "nonahydrate," which indicates that there are nine water molecules associated with each formula unit of Fe(NO₃)₃. This compound is also commonly known as ferric nitrate nonahydrate.
Balanced equation for the given reaction is;
Fe(NO₃)₃·9H₂O(s) → Fe(NO₃)₃(s) + 9H₂O(g)
According to the equation, one mole of Fe(NO₃)₃·9H₂O produces 9 moles of water vapor (H₂O) when it undergoes the reaction. Therefore, if there are initially 14.2 moles of Fe(NO₃)₃·9H₂O, the number of moles of water vapor (H₂O) produced will be;
14.2 moles of Fe(NO₃)₃·9H₂O × 9 moles of H₂O per 1 mole of Fe(NO₃)₃·9H₂O = 127.8 moles of H₂O
Therefore, 127.8 moles of water vapor will be produced.
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Hi i need help figuring how many mol… please if you can hurry! Thank you
Answers
The number of moles is 0.001734 moles
The Ideal gas law is the equation of state of a hypothetical ideal gas. It is a good approximation to the behaviour of many gases under many conditions, although it has several limitations. The ideal gas equation can be written as
PV = nRT
where,
P = Pressure
V = Volume
T = Temperature
n = number of moles
Given,
Volume = 3.4L
Pressure = 1.2 atm
Temperature = 283K
PV = nRT
1.2 × 3.4 = n × 8.314 × 283
n = 0.001734 moles
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Determine the mass of carbon dioxide that should be produced in the reaction between 3.74g of carbon and excess oxygen what is the maximum recent yield if 11.34g of CO2 is recovers
Answers
13.71g is the mass of carbon dioxide that should be produced in the reaction between 3.74g of carbon and excess oxygen. 83% is the percent yield.
Percent yield in chemistry is the percentage of the product's weight to its theoretical yield. In order to quantify the outcome in percent, we divide the experimental yield with the theoretical yield then multiply the result by 100. Chemists employ an equation called percent yield after a reaction to determine how much material they should have theoretically extracted against how much they actually acquired.
C+ O[tex]_2[/tex] → CO[tex]_2[/tex]
moles of carbon = 3.74/ 12=0.31moles
mass of CO[tex]_2[/tex] =0.31×44=13.71g
% yield = (11.34/13.71)× 100=83%
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a 40 ml solution containing .30 M Ti+3 was titrated with 0.75 M Sn+2. what potential at the equivalence point if the resulting solution is
measured against a reference electrode
Answers
Ti+3 + Sn+2 → Ti+4 + Sn+4
The balanced equation shows that one mole of Ti+3 reacts with one mole of Sn+2. We can use this to calculate the number of moles of Sn+2 required to react completely with the Ti+3 in the solution:
n(Sn+2) = (0.30 mol/L) x (0.040 L) = 0.012 mol
The volume of Sn+2 required to react with the Ti+3 can be calculated using the molarity and the number of moles:
V(Sn+2) = n(Sn+2) / [Sn+2] = 0.012 mol / 0.75 mol/L = 0.016 L = 16 mL
At the equivalence point, all of the Ti+3 has reacted with the Sn+2, so the resulting solution contains only Ti+4 and Sn+4. The potential at the equivalence point can be calculated using the Nernst equation:
E = E° - (RT/nF) x ln(Q)
where E° is the standard cell potential, R is the gas constant, T is the temperature in Kelvin, n is the number of electrons transferred in the reaction, F is the Faraday constant, and Q is the reaction quotient.
The standard cell potential can be calculated using the reduction potentials for the half-reactions:
Ti+4 + 2 e- → Ti+3 E° = -0.15 V
Sn+4 + 2 e- → Sn+2 E° = 0.15 V
The overall cell potential is the sum of the reduction potentials:
E°cell = E°reduction (cathode) - E°reduction (anode) = 0.15 V + 0.15 V = 0.30 V
At the equivalence point, the reaction quotient Q is equal to the equilibrium constant K:
K = [Ti+4] / [Sn+4]
The concentrations of Ti+4 and Sn+4 can be calculated from the number of moles and the total volume of the solution:
n(Ti+4) = n(Sn+2) = 0.012 mol
V(total) = 0.040 L + 0.016 L = 0.056
CO, (9) +2NH_(9) - CO(NH,) (s) +H, O(1)
a. What is the maximum mass of urea, CO(NH), that can be manufactured from the reaction of 2.20 moles of CO2 with sufficient amount of ammonia.
Answers
The mass of the ammonia that is required is 258 g.
What is the stoichiometry of the reaction?
The quantitative correlations between the reactants and products in a chemical reaction are the focus of the chemistry subfield known as stoichiometry.
We have to know that;
1 mole of CO2 produces 1 mole of urea
2.2 moles of CO2 produces 2.2 urea
Given that the number of moles of urea = 455 g/60 g/mol
= 7.58 moles
Now;
2 moles of NH3 produces 1 mole of urea
x moles of NH3 produces 7.58 moles of urea
x = 7.58 * 2/1
= 15.16 moles
Mass of the ammonia = 15.16 moles * 17 g/mol
= 258 g
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at 300K, a sample of gas occupies 1.5 dm3.
Assuming the pressure remains constant, the volume of this gas at 600K would be?
Answers
So, to find the volume of the gas at 600K, we can use the formula:
(Volume at 600K) = (Volume at 300K) x (Temperature at 600K / Temperature at 300K)
(Temperature at 600K) = (600°C + 273.15) = 873.15K
(Temperature at 300K) = (300°C + 273.15) = 573.15K
So, the volume of the gas at 600K would be:
(Volume at 600K) = (1.5 dm³) x (873.15K / 573.15K) = 2.28 dm³
Therefore, the volume of the gas at 600K would be 2.28 dm³.
Write short note on the
-physical and chemical methods
of monitoring the rate of
chemical reaction
Answers
Answer:
Physical and chemical methods can be used to monitor the rate of a chemical reaction. Physical methods measure changes in properties like temperature, pressure, or volume. Chemical methods track reactant consumption or product formation using techniques like titration or spectrophotometry. The choice of method depends on the reaction being studied, and scientists use these methods to gain insight into reaction kinetics and optimize conditions for better efficiency and selectivity.
The rate constant for the first-order reaction below is 0.0739 s-1
If the reaction is begun with an initial concentration of A equal to 0.95 M. what is the concentration of A after 38.02 s?
______M
Answers
The concentration of A after 38.02 s is 0.057 M.
What is the concentration of A after 38.02 s?The concentration of A after 38.02 s is calculated by using rate equation as follows;
[A] = [A]₀e^(-kt)
where;
k is the rate constantA is the concentration of reactant AA₀ is the initial concentration of A at t=0t is the time elapsed since the reaction startedThe concentration of A after 38.02 s is calculated as;
[A] = [A]₀e^(-kt)
= 0.95 M e^(-0.0739 s⁻¹ x 38.02 s)
= 0.057 M
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How many years passed between the first man on the Moon and the first US woman in space?
Answers
It took 14 years between the first man on the Moon and the first US woman in space.
What is space exploration?The use of astronomy and space technology to explore outer space is known as space exploration. While astronomers use telescopes to explore space, physical exploration is carried out by both uncrewed robotic space probes and human spaceflight.
Understanding gravity, the magnetosphere, the atmosphere, fluid dynamics, and the geological evolution of other planets, for example, has come from studying the solar system.
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in general, which of the following statements about electron-pair geometries is true? question 14 options: a) they maximize the space between valence electrons to minimize the repulsion between them. b) they maximize the polarity of valence electrons to minimize the attraction between them. c) they maximize the space between
Answers
They maximise the distance between valence electrons to reduce the repulsion between them, which is option an in the correct response. This is so because the idea behind electron-pair geometries is to reduce valence electron repulsion.
By increasing the distance between them, which decreases the repelling power of the interactions between electrons, this is accomplished.
Because they reduce electron repulsion and enable molecules to adopt their most stable form, electron-pair geometries are used to anticipate the structure of molecules.
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What is hydrogen fuel cell technology
Answers
Answer:
By combining hydrogen and air in the presence of a catalyst, a fuel cell generates electricity to drive an electric motor, with water vapor as the only by-product. So, compared to a battery, a fuel cell is an energy converter rather than a storage device.
Explanation:
If 4.53g Ar are added to 1.12 atm He in a 2.00 L cylinder at 27.0 Celsius degree
What is the total of gaseous mixture?
Answers
The total gaseous mixture is 4.48 g.
The total gaseous mixture can be calculated using the ideal gas law: PV = nRT.
First, we need to convert the temperature to Kelvin: 27.0°C + 273.15 = 300.15 K.
Next, we can use the ideal gas law to calculate the number of moles of each gas:
For He: n = (1.12 atm) (2.00 L) / (0.08206 L·atm/mol·K) (300.15 K) = 0.0906 mol
For Ar: n = (4.53 g) / (39.95 g/mol) = 0.113 mol
The total number of moles of gas in the mixture is then:
n(total) = n(He) + n(Ar) = 0.0906 mol + 0.113 mol = 0.204 mol
Finally, we can calculate the total mass of the mixture:
m(total) = n(total) × M(avg)
where M(avg) is the average molar mass of the mixture, which can be calculated as:
M(avg) = (M(He) + M(Ar)) / 2 = (4.003 g/mol + 39.95 g/mol) / 2 = 21.98 g/mol
Thus,
m(total) = 0.204 mol × 21.98 g/mol = 4.48 g
Therefore, The total weight of the gaseous mixture is 4.48 g.
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3. If I have 3 moles of gas in a container with a volume of 60 liters and at a temperature of 400 K, what is the pressure inside the container?
Answers
Answer:
The pressure would be 1.65 atmospheres.
How many liters of a 3.4 m isopropanol solution can be made with 78 g of isopropanol
Answers
Answer:
You can make 2.29 L of 3.4 M isopropanol solution with 78 g of isopropanol.
Explanation:
pls tysm it is due today
Answers
The reaction that is shown by the option D is a balanced reaction equation.
What is a balanced reaction equation?We can say that a reaction equation as we have it balanced number of each of the atoms that we have on the left hand side of the reaction equation is the same as the number of the atoms of the elements that we have on the right hand side of the reaction equation.
A reaction equation is a representation of a chemical reaction using chemical formulas and symbols. It shows the reactants on the left-hand side and the products on the right-hand side of the equation, separated by an arrow.
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A student used 0.17 grams of Alka Seltzer for their experiment. What's the mass of sodium bicarbonate (NaHCO3) in their sample?
Answers
Answer:
To find the mass of sodium bicarbonate (NaHCO3) in a sample of Alka Seltzer that weighs 0.17 grams, we need to know the percentage of NaHCO3 in Alka Seltzer. This information is usually provided on the label of the product. Once we know the percentage of NaHCO3, we can use the following formula to calculate the mass of NaHCO3 in the sample:
mass of NaHCO3 = sample mass (in grams) x % NaHCO3 / 100
For example, if the percentage of NaHCO3 in Alka Seltzer is 50%, then the mass of NaHCO3 in a 0.17 gram sample would be:
mass of NaHCO3 = 0.17 x 50 / 100 = 0.085 grams
Therefore, the mass of sodium bicarbonate in the student's 0.17 gram sample of Alka Seltzer depends on the percentage of NaHCO3 in the Alka Seltzer, which should be provided on the product label.
Explanation:
Determine the number of moles in 100,0 g S
Answers
The number of moles in 100g of Sulphur is 3.13 moles.
How to calculate number of moles?The number of moles in a substance can be calculated by dividing the mass of the substance by its molar mass as follows:
moles = mass ÷ molar mass
According to this question, there are 100g of Sulphur. Sulphur has an atomic mass of 32g/mol. The moles of this element can be calculated as follows;
moles = 100g ÷ 32g/mol
moles = 3.13moles
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)A mixture of 0.220 molesCO, 0.350 molesF2and 0.640 molesHehas a total pressure of 2.95 atm.What is the partial pressure ofCO?
Answers
The partial pressure of a component gas in a mixture is the pressure that gas would exert if present alone in the vessel at the same temperature as that of the mixture. Here the partial pressure of CO is
The pressure exerted by a mixture of two or more non-reacting gases enclosed in a definite volume is equal to the sum of the partial pressures of the component gases. This is sated by Dalton.
Here partial pressure is:
partial pressure = Mole fraction × Total pressure
Mole fraction of CO = Number of moles of CO / Total moles
n(CO) = 0.220 / 1.21 = 0.181 moles
partial pressure = 2.95 × 0.181 = 0.533 atm
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Determine the pH of a solution that is 0.00501 M HCl and 0.0378 M HClO2. The a of HClO2 is 1.1×10−2
.
Answers
The acidity or alkalinity of a solution depends on the hydronium ion and hydroxide ion concentration. The pH scale is introduced by the scientist Sorensen. The pH of the solution is -1.90.
The pH of a solution is defined as the negative logarithm to the base 10 of the value of the hydronium ion concentration in moles per litre. The pH of the solution is given as:
pH = -log [H₃O⁺]
Dissociation of HCl is:
HCl + H₂O → H₃O⁺ + Cl⁻
Kₐ = [H₃O⁺][Cl⁻] / [HCl]
1.3 × 10⁶ = x × x / 0.00501
x² = 0.00501 × 1.3 × 10⁶ = 6513
x = √6513 = 80.7 M
HClO₂ + H₂O → H₃O⁺ + ClO⁻
Kₐ = [H₃O⁺][ClO⁻] / [HClO₂]
1.1×10⁻² = x² / 0.0378
x² = 0.0378 × 1.1×10⁻² = 0. 00041
x = 0.020 M
Thus the total concentration now is :
x = [H₃O⁺] = 0.020 + 80.7 = 80.72 M
pH = -log [H₃O⁺]
-log[80.72 ] = -1.90
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Sometimes a fossil is formed as a result of the movement of an organism in soft sediment. Which of these are two kinds of trace fossils?
*
1 point
shells and bones
tracks and burrows
a bee and a beetle in amber
petrified and mummified fossils
Answers
Answer:The two kinds of trace fossils mentioned in the options are:
tracks
burrowsTracks and burrows are both examples of trace fossils, which are fossils thatprovide evidence of an organism's activity, rather than the organism itself.Tracks are impressions left by an organism's feet or other body parts as itmoved across soft sediment, while burrows are tunnels or other structurescreated by an organism as it burrowed into the sediment. Both types of tracefossils can provide valuable information about an organism's behavior, habitat, and interactions with other organisms.
Can anyone name this compound. Only number 4. and i would appreciate if you could explain how you name it.
Answers
The IUPAC name of the compound is 3-chloro-4-ethyl-2,4-dimethyloctane
How do i determine the name for the compound?The naming of compound follows the IUPAC principles. This is illustrated below:
Locate the longest continuous carbon chain. In this case it is carbon 8. Thus, we can say that the parent name is octaneIdentify the substituent groups attached. In this case the substituent groups attached are: Cl, CH₃ and CH₂CH₃ Give the substituents the lowest count. In this case, Cl is located at carbon 3, CH₂CH₃ is located at carbon 4 and the two CH₃ are located at carbon 2 and 4Combine the above to obtain the IUPAC name for the compound.Thus, the IUPAC name for the compound is: 3-chloro-4-ethyl-2,4-dimethyloctane
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Physicians tend to use units of calories ,in part because that is what their patients use and understand .Food “Calories “ are actually calories. How many calories are in a calorie?
A.10,000
B.1,000
C.100
D.10
E.1
Please help me what is the answer.
Answers
PLEASE HELP WITH CONVERSIONS
Answers
The grams of pigment needed is 9.20 grams
The grams of water needed is 0.199 grams.
The final molarity of the binder in the paint mixture is 20.04 M.
What are the masses of substances required?The masses of substances required are reived from the mole ratios given.
The grams of pigment needed:
mole ratios of CaCO3 and Cr2O3 is 1 : 1.52
Using the conversion factors:
molar mass of CaCO3 = 100.1 g
molar mass of Cr2O3 = 151.99 g
grams of pigment needed = (0.400 g CaCO3 x 1 mol CaCO3/100.1 g CaCO3) x (1.52 mol Cr2O3/1 mol CaCO3) x (151.99 g Cr2O3/1 mol Cr2O3) grams of pigment needed = 9.20 g Cr2O3
the grams of water needed:
mole ratio of CaCO3 and H2O is 1 : 27.5
molar mass of H2O = 18.0 g
the grams of water needed = 0.400 g CaCO3 x (1 mol CaCO3/100.1 g CaCO3) x (27.5 mol H2O/1 mol CaCO3) x (18.0 g H2O/1 mol H2O)
the grams of water needed = 0.199 g H2O
From the density of water, the volume of water needed is 0.199 mL of water.
Molarity = moles of solute/volume of solution in liters
Volume of solution = 0.000199 L
Number of moles of CaCO3 = 0.400/100.1 g
Number of moles of CaCO3 = 0.003998 mol
Molarity = 0.003998/0.000199
Molarity = 20.04 M
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