Answer:
Explanation:
So chemical changes require a change on a molecular level that cannot be reversed because they form some new substance. Souring milk is not something you can reverse, and the process of it souring produces new molecules.
What carpet Burns in a deficiency of O2 a mixture of CO and CO2 forms.Carbon Burns in excess O2 to form only CO2 and CO Burns in excess O2 to form only CO2. Calculate ΔH for C(graphite +1/2O2) →CO(g).
Answer:
Explanation:
From the combustion of carbon, the reactions occurring in limited oxygen conditions are:
[tex]C(graphite) + \dfrac{1}{2}O_{2(g)} \to CO_{(g)}[/tex]
[tex]C(graphite) + O_{2(g)} \to CO_{2(g)}[/tex]
If it occurs in excess, then any leftover CO changes to CO2. i.e.
[tex]C(graphite) + O_{2(g)} \to CO_{2(g)}[/tex] ---- (1)
[tex]CO_{(g)} + \dfrac{1}{2}O_{(g)} \to CO_{2(g)}[/tex] ----- (2)
From (1), the enthalpy change is:
[tex]\Delta H_{rxn1} = \Delta H^0_{fCO_2(g)} - ( \Delta H^0_{f C(graphite)}+ \Delta H^0_{fCO_2(g)}[/tex]
[tex]\Delta H_{rxn1} =-393.5 \ kJ/mol -(0+0)[/tex]
[tex]\Delta H_{rxn1} =-393.5 \ kJ/mol[/tex]
From (2), the enthalpy change is:
[tex]\Delta_{rxn2} = \Delta H^0_{fCO_2(g)} - ( \Delta H^0_{fCO(g)} + \dfrac{1}{2} \Delta H^0_{fO_2(g)})[/tex]
[tex]\Delta_{rxn2} = -393.5 \ kJ/mol -(-110.5 + \dfrac{1}{2}(0))[/tex]
[tex]\Delta_{rxn2} = -283.0 \ kJ/mol[/tex]
Subtracting (2) from (1), we get:
[tex]C(graphite) + O_{2(g)} \to CO_{2(g)} \ \ \ \Delta H_{rxn} = -393.5 \ kJ/mol}[/tex]
[tex]CO_{(g)} + \dfrac{1}{2} O_2(g) \to CO_{2(g)}} \ \ \ \Delta H _{rxn2} = -283.0 \ kJ/mol[/tex]
[tex]C(graphite) + O_{2(g)} \to CO (g) + \dfrac{1}{2}O_{2(g)} \ \ \ \Delta H_{rxn} = -110.5 \ kJ/mol[/tex]
[tex]C(graphite) + \dfrac{1}{2} O_{2(g)} \to CO (g) \ \ \ \Delta H_{rxn} = -110.5 \ kJ/mol[/tex]
The enthalpy change ΔH of the reaction = -110.5 kJ/mol
Why is your body going through physical and chemical changes?
Answer:
Physical and chemical changes can occur almost everywhere, even in our bodies! Food must be broken down into a form that our cells can use. When we eat, our bodies physically break down food into small pieces. Our bodies also chemically break down those small pieces of food into tiny organic molecules.
Explanation:
how are Ionic and Covalent Bonds are formed with examples ?
Answer:Comparison of Ionic and Covalent Bonds
In an ionic bond, the atoms are bound together by the electrostatic forces in the attraction between ions of opposite charge. ... For example, sodium (Na), a metal, and chloride (Cl), a nonmetal, form an ionic bond to make NaCl. In a covalent bond, the atoms bond by sharing electrons.
pls add Brainliest
Which of the following would be most likely to experience strong intermolecular forces?
A. Molecules that contain no electrically charged regions.
B. Molecules that contain atoms of oxygen.
C. Molecules that are composed of solely ions.
D. Molecules that have both negatively and positively charged parts.
Answer:
The correct answer is D
Explanation:
Just took quiz
Throwing a snowball during snowball fight is most like an example of
What is molarity measured the concentration of
QUESTION 3
Identify the number that has 3 significant figures.
O A. 100
OB. 12.0
O C. 120
OD. 123.00
Answer:
D
Explanation:
One mole of a substance has a different number of particles as one mole of another substance.
O True
O False
A 2.26 M solution of KOH is prepared. Calculate the moles and mass of solute present in a 15.2-mL sample of this solution. The molar mass of KOH is 56.11 g/mol.
Answer:
0.0344 moles and 1.93g.
Explanation:
Molarity is defined as the ratio between moles of a solute (In this case, KOH), and the volume. With molarity and volume we can solve the moles of solute. With moles of solute we can find mass of the solute as follows:
Moles KOH:
15.2mL = 0.0152L * (2.26mol / L) = 0.0344moles
Mass KOH:
0.0344 moles * (56.11g/mol) = 1.93g of KOH
1pt Copper chloride and aluminum react to produce
aluminum chloride and copper. Which of the
following is the correctly balanced chemical
equation for this reaction?
O A. CuCl, + Al -> AICI, + u
O B. 3CuCl, + Al -> AlCl, + 2Cu
OC. 3CUCI, + 2Al -> 2AICI, + 3Cu
OD. CuCl, + 3Al -> AICI, + 2Cu
Answer:
None of the above
but it must be:
for Copper(I)chloride
3CuCl + Al ==> AlCl3 + 3Cu
for Copper (II) chloride
3CuCl2 + 2Al ==> 2AlCl3 + 3Cu
What is the molar mass of magnesium sulfate, MgSO4?
Answer:
120.37 g/mol is the molar mass of magnesium sulfate
Fungus is an example of a/an-
A:tissue
B:cell type
C:organ
D:organism
Answer:
D.organism
Explanation:
A fungus from the kingdom fungi is an organism
Answer:
D. organism
......................
pleaseee help thank youu
Answer:
i just took it the answers is C
Explanation:
Solid mercury (II) oxide produces liquid mercury and oxygen gas
Mercury(II) oxide, a red solid, decomposes when heated to produce mercury and oxygen gas. Mercury(II) oxide is a red solid. When it is heated, it decomposes into mercury metal and oxygen gas. A reaction is also considered to be a decomposition reaction even when one or more of the products are still compounds.
Write down the possible types of atomic
Orbitals of n=4
Answer:
2
Explanation:
because first shell ( k shell ) needs only 2 electron to complete its octet .
hope it helps
what is the volume of the rock? if the water rose from 50L to 70mL
A chemist prepares a solution of barium acetate BaCH3CO22 by weighing out 52.9g of barium acetate into a 100.mL volumetric flask and filling the flask to the mark with water. Calculate the concentration in /gL of the chemist's barium acetate solution. Round your answer to 3 significant digits.
Answer:
529g/L
Explanation:
The concentration in chemistry is defined as the amount of solute in a determined amount of solution. The concentration in g/L means the amount of grams of solute (In this case, barium acetate), per liter of solution.
To solve this problem we need to find grams of solute (52.9g, already given) and the volume in liters (Converting 100mL to liters):
Volume:
100mL * (1L / 1000mL) = 0.100L
And concentration in g/L is:
52.9g / 0.100L =
529g/LWill give brainliest
What is the correct formula to determine density?
Answer:
density =mass/volume
Explanation:
p=m/v
p means raw
m means mass
v means volume.
what element is in group 13, period 4
Answer:
Gallium
Explanation:
Answer:
Gallium
Explanation:
If 10.88 moles of NH3 were produced, how many moles of N2 would be
required?
Answer:
5.44 moles of nitrogen required.
Explanation:
Given data:
Number of moles of NH₃ = 10.88 mol
Moles of N₂ required = ?
Solution:
Chemical equation:
N₂ + 3H₂ → 2NH₃
Now we will compare the moles nitrogen and hydrogen.
NH₃ : N₂
2 : 1
10.88 : 1/2×10.88 = 5.44mol
5.44 moles of nitrogen required.
All the radioactive elements are found in the last group of the Periodic Table.
True
False
Answer:
False
Explanation:
flourine is more reactive than chlorine . why ? with short reason.
Answer:
Electronegativity is probably the biggest thing that plays into reactivity. Therefore, since fluorine has a higher electronegativity than chlorine, fluorine is more reactive.
Explanation:
I got it right
if 3.26 g is dissolved in enough water to make exactly 323 ml of solution, what is the molar cocentration of nitrate ion g
A 52 gram sample of an unknown metal requires 714 Joules of energy to heat it from
30.5◦C to 82◦C. What is the specific heat of
this metal?
Answer in units of J/g ·
◦ C.
Answer: Approximately [tex]0.267 \frac{\text{J}}{\text{g}^{\circ}\text{C}}[/tex]
===================================================
Work Shown:
We have the following variables
Q = 714 joules = heat requiredm = 52 grams = massc = specific heat = unknown[tex]\Delta t[/tex] = 82-30.5 = 51.5 = change in temperaturenote: the symbol [tex]\Delta[/tex] is the uppercase Greek letter delta. It represents the difference or change in a value.
Apply those values into the formula below. Solve for c.
[tex]Q = m*c*\Delta t\\\\714 = 52*c*51.5\\\\714 = 52*51.5*c\\\\714 = 2678*c\\\\2678*c = 714\\\\c = \frac{714}{2678}\\\\c \approx 0.26661687826737\\\\c \approx 0.267\\\\[/tex]
The specific heat of the unknown metal is roughly [tex]0.267 \frac{\text{J}}{\text{g}^{\circ}\text{C}}[/tex]
Which of the following is a radioactive element?Sodium, Fluorine,Oxygen
francium
Answer:
Fluorine
Explanation:
These particles stick in the atoms and make them radioactive.
please helpppppppppp
Answer:
Environmental factors such as diet, temperature, oxygen levels, humidity, light cycles
And the presence of mutagens can all impact which of an animal's genes are expressed, which ultimately affects the animal's phenotype.
what is the empirical formula of A compound is found to contain 39.12 % carbon, 8.772 % hydrogen, and 52.11 % oxygen by mass.
Answer:
C₃H₈O₃
Explanation:
Let's assume we have 100 g of said compound. Then we would have:
39.12 g of C8.772 g of H52.11 g of ONow we convert those masses into moles, using their respective atomic weights:
C ⇒ 39.12 g ÷ 12 g/mol = 3.26 mol CH ⇒ 8.722 g ÷ 1 g/mol = 8.722 mol HO ⇒ 52.11 g ÷ 16 g/mol = 3.26 mol OThen we divide those moles by the smallest number among them:
C ⇒ 3.26 mol C / 3.26 = 1H ⇒ 8.722 mol H / 3.26 = 2.68O ⇒ 3.26 mol O / 3.26 = 1Finally we multiply those numbers by 3, so as to convert the 2.68 of H into an integer:
C ⇒ 1 * 3 = 3H ⇒ 2.68 * 3 = 8O ⇒ 1 * 3 = 3Thus the empirical formula is C₃H₈O₃
Atoms are stationary and don't move when in solid form.
False
True
Answer:
True? The don't stay exactly still i dont think, but i'd say true.
Explanation:
Answer:
TRUE
Explanation:
In a solid, atoms are packed tightly together and move very slowly. In fact, they do not flow at all: they simply vibrate back and forth.
Key words vibrate, not movement.
Correct me if I'm wrong of course
How would a long period without sunlight affect the food web? PLEZZ HELP MEH IF YOU WANT BRAINEIST AND LIKE COMMENTED
It would cause consumers to consume more food.
It would have no effect on the food web.
It would stop decomposers from breaking down matter.
It would stop producers from producing food.
Answer:
im pretty sure its the last one
Explanation:
if plants dont have sun light they will die because the sunlight gives them the nutrients to survive