Answer:electron
Explanation:
500 grams of an unknown substance gains 23000 J of heat as it is heated from a temperature of 250C to 1250C. Using mathematical computation and the chart below, determine the identity of the unknown substance.
Answer:
The given substance is cast iron.
Explanation:
Given data:
Mass of substance = 50 g
Heat absorbed = 23000 J
Initial temperature = 250°C
Final temperature = 1250°C
Which metal is this = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 1250°C - 250°C
ΔT = 1000°C
23000 j = 50 g ×c ×1000 °C
23000 J = 50,000 g. °C×c
c = 23000 J /50,000 g. °C
c = 0.46 J/g.°C
The given substance is cast iron.
Why is it important to know which category of microorganism has caused an infection?
Select one:
a. Treatment depends on which kind of organism caused the infection.
b. Probiotic infections can actually worsen some conditions.
c. Some infections can indicate cancer.
d. Some types of infections are highly contagious.
PLEASE ANSWER QUICKLY
Answer:
A
Explanation:
Adaleigh is learning about renewable and non-renewable resources in her science class. She decides to take
a nature walk and makes notes of all the renewable resources that she sees. Which of the following is an
observation that Adaleigh could have made on her walk?
A. The seeds on the ground are going to grow into new trees.
B. The tallest trees had the most seeds around their bases.
C. When trees decay, they could eventually turn into coal.
D. Pine trees are older than oak trees.
Answer:
A. The seeds on the ground are going to grow into new trees.
Explanation:
Trees are renewable resources.
The percent by mass of Ca in CaCl2 is equal to
1. (40/111) x 100
2. (111/40) x 100
3. (3/1) x 100
4. (1/3) x 100
Answer:
(40/111)×100Here is a bonus Answer✍️✍️Percent composition by elementElement Symbol Mass PercentChlorine Cl 63.888%Calcium Ca 36.112Mass percentage does not have any unit as numerator and denominator contains the same unit. The percent by mass of Ca in CaCl[tex]_2[/tex] is equal to (40/111) x 100. The correct option is option A.
What is percentage by mass?Mass percentage represents the the percentage of each element that is making a particular compound.
Mathematically,
Percentage of mass = (component’s mass ÷ total mass) x 100%
Atomic weight of different element of calcium chloride{ CaCl[tex]_2[/tex]} are
Ca = 40 ; Cl = 35
Total mass of Calcium element in calcium chloride = 40g/mol
Total mass of Chlorine atom in calcium chloride = 35× 2= 71g/mol
Total molar mass of calcium phosphate = 40 +71= 111g/mole
Percentage of calcium in calcium chloride =40÷111 = 36%
Therefore, the percent by mass of Ca in CaCl2 is equal to (40/111) x 100. The correct option is option A.
To learn more about mass percentage, here:
https://brainly.com/question/27429978
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How are ionic compounds named?
Answer:
Ionic compounds are neutral compounds made up of positively charged ions called cations and negatively charged ions called anions. For binary ionic compounds (ionic compounds that contain only two types of elements), the compounds are named by writing the name of the cation first followed by the name of the anion.
Explanation:
Hope this helps.
When [H+] = 4.0 × 10–9 M in water at 25°C, then
Kw =1.0×10–14.
b. pOH = 7.
c. [H3O+] = [OH–].
d. pH= 7
e. A-D are all correct
Answer:
a. Kw = 1.0 × 10⁻¹⁴
Explanation:
a. Let's consider the self-ionization of water.
2 H₂O(l) ⇄ H₃O⁺(aq) + OH⁻
The ion-product of water (Kw) at 25 °C is:
Kw = [H₃O⁺][OH⁻] = 1.0 × 10⁻¹⁴
c. Considering [H⁺] = [H₃O⁺] = 4.0 × 10⁻⁹ M, the concentration of OH⁻ is:
[OH⁻] = 1.0 × 10⁻¹⁴/[H₃O⁺] = 2.5 × 10⁻⁶ M
b. We can calculate the pOH using the following expression.
pOH = -log [OH⁻] = -log 2.5 × 10⁻⁶ = 5.6
d. We can calculate the pH using the following expression.
pH = -log [H⁺] = -log 4.0 × 10⁻⁹ = 8.4
When [H+] = 4.0 × 10–9 M in water at 25°C, then the [tex]Kw =1.0\times 10^-^1^4.[/tex]
What is dissociation constant?
Kw is the dissociation constant or ionization constant of water.
The self-ionization of water will be
[tex]\rm 2 H_2O(l) = H_3O^+(aq) + OH^-[/tex]
The dissociation constant of the water at 25°C will be
[tex]\rm Kw = [H_3O^+][OH^-] = 1.0 \times 10^-^1^4[/tex]
Thus, the correct option is a. [tex]Kw =1.0\times 10^-^1^4.[/tex]
Learn more about dissociation constant
https://brainly.com/question/3657057
i need the answer for this
Answer:
need points
Explanation:
Question 5
2 pts
To determine the density of an irregularly shaped object, a student immersed the object in 32.2 mL of water in a graduated cylinder, causing the level of the water to rise to 37.8 ml. If the object had a mass of 12.4 g, what is the density of the object?
O 0.32 g/mL
O 1.4 g/mL
O 3.4 g/mL
O 2.2 g/mL
Help quick right answer gets brainliest !!
Answer:
Explanation:
2.2 g/mL is the answer.
is 4 Fe + 3 O2 --> 2 Fe2O3
balanced?
Answer:
Yes the given equation is balanced.
Explanation:
Chemical equation:
Fe + O₂ → Fe₂O₃
Balanced chemical equation:
4Fe + 3O₂ → 2Fe₂O₃
There are four iron and six oxygen atoms on both side of equation thus the given equation is balanced.
The given reaction also follow the law of conservation of mass.
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
This reaction is synthesis reaction:
Synthesis reaction:
It is the reaction in which two or more simple substance react to give one or more complex product.
A + B → AB
If the specific heat of water is 4.18 3/g*^ C much heat is required to increase the temperature of 12 g of water from 23 degrees * C to 39 degrees * C ^ 2
Answer:
Q = 802.6 J
Explanation:
Given data:
Specific heat capacity of water = 4.18 J/g.°C
Mass of water = 12 g
Initial temperature = 23°C
Final temperature = 39°C
Heat required = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 39°C - 23°C
ΔT = 16 °C
Q = 12 g× 4.18 J/g.°C × 16 °C
Q = 802.6 J
What is the empirical formula for a compound that is comprised of 54.0% sodium, 8.50% boron, and 37.5% oxygen by mass?
A) Na2B2O3.
B) Na3BO3.
C) Na3B2O2.
D) Na4BO4.
Answer:
B) Na3BO3.
Explanation:
Hello!
In this case, since percent compositions are used to identify the empirical formula of an unknown compound, we can assume we have 54.0 g of sodium, 8.50 g of boron and 37.5 g of oxygen, and we compute the moles of each one:
[tex]n_{Na}=54.0g*\frac{1mol}{23g} =2.35mol\\\\n_B=8.50g*\frac{1mol}{11g}=0.773mol\\\\n_O=37.5g*\frac{1mol}{16g}=2.34mol[/tex]
Now, we divide by the moles of boron as those are the fewest:
[tex]Na:\frac{2.35}{0.773}=3\\\\B:\frac{0.773}{0.773}=1\\\\O=\frac{2.34}{0.773}=3[/tex]
Thus, the empirical formula is B) Na3BO3.
Best regards!
List three things, other than the name, symbol, atomic number, and average atomic mass, you can discover about an element using the periodic table in Figure 6.9.
Answer: State of matter, Subcategory in the metal-metalloid-nonmetal trend, and electrons per shell.
Explanation:
Which molecule/molecular compound is joined by a single covalent bond? O2 or N2 or Br2 or CO2?
1. What kinds of metals are REALLY reactive? why?
2. What kinds of non-metals are REALLY reactive? why?
3. What group on the periodic table doesn’t react at all? why?
Answer:
1. Alkali metals (group 1)
2. halogens (Group 17)
3. noble gasses (group 18)
Explanation:
1. alkali metals only have one valence electron meaning that they really want to lose that one valence electron to get a full octet.
2. halogens have 7 valence electrons meaning that they just need to gain 1 to get a full octet.
3. Nobel gasses already have a full octet meaning that they don't want to react. (atoms only react to get a full octet)
I hope this helps. Let me know if anything is unclear.
100
80
100 mL
water vapor
Which statement describes what will happen if a student pushes the plunger
to compress the water vapor?
A. The total number of water particles will increase.
B. The amount of energy in the water particles will decrease.
C. The amount of empty space between the water particles will
decrease
D. The total volume of the water particles will increase
I will mark brainliest
Answer:
Explanation:it is c
Answer:
C The amount of empty space between the water particles will decrease
Explanation:
I just took the quiz, have a nice day!
A 2.52 L container of oxygen gas at 28.6 °C is heated to 45.9 °C. Assuming that the volume of the container can vary, what is the new volume of the gas?
Answer:
4.04433566 L (433566 repeating)
Explanation:
2.52 is divided by 28.6 is 0.0881118 (881118 repeating). multiply 0.0881118 (881118 repeating) by 45.9 to get 4.04433566 L (433566 repeating).
According to the CDC, influenza is a respiratory illness caused by the flu virus. Some of the symptoms include cough, sore throat, muscle aches, and vomiting.
Which statement represents a reasonable claim about the effects of the flu virus on the body’s ability to maintain homeostasis?
A
Influenza affects one major system, which must work to restore homeostasis.
B
Influenza affects one system, but multiple systems must interact in order to restore homeostasis.
C
Influenza affects multiple systems and multiple systems must interact in order to restore homeostasis.
D
Influenza affects one major system and secondary systems, but the major system works to restore homeostasis.
Answer:
B. Influenza affects one system, but multiple systems must interact in order to restore homeostasis.
Explanation:
According to the CDC, influenza is a respiratory illness caused by the flu virus of which some symptoms include cough, sore throat, muscle aches, and vomiting.
The statement that represents a reasonable claim about the effects of the flu virus on the body’s ability to maintain homeostasis is that it affects one system which is the RESPIRATORY SYSTEM but multiple systems must intervene in other to maintain homeostatis.
*Homeostatis is the unique way a human body or organism stabilises its internal state despite the changes on the external.
Please help me ASAP
When is my dad going to get the milk?
Answer:
joe.......
Explanation:
mama......
A. What is the frequency of light that has a wavelength of 6.2 x 10^-7 m?
B. Identify the color of this light.
C. Calculate the amount of energy given off by this atom.
Answer:
I think the answer is letter C
Compare and contrast the mass of the object to the size of the object.
HELPPPPPPPPP 35 POINTSSSSSS!!!!!FILL IN THE BLANKS with either "reduce" or "oxidize"
Magnesium is able to ——copper, and copper is able to —— magnesium.
Zinc is able to—— magnesium, and magnesium is able to—— zinc.
Copper is able to—— zinc, and zinc is able to—— copper.
Look at my screenshot:
FeO+ PdF2 ---> FeF2+PdO balance please worth 50 points
Answer: FeO
Explanation:
Answer:
This is not worth 50 points liar
Explanation:
help me pleaseeeeee
Answer:
Arthropod (3)
Annelids (2)
Cnidarians (1)
Echinoderms (4)
Explanations:
I hope all this helps if u don't understand it let me know.
how many elements are found in the third period. A.2 B.18 C.8 D.32
Answer:
8
Explanation:
u can find it on ur chemistry book
Answer:
C. 8
Explanation:
Check chemistry textbook
The free flow of electrons is responsible for
Answer:
An electrical phenomenon is caused by flow of free electrons from one atom to another. The characteristics of current electricity are opposite to those of static electricity. Wires are made up of conductors such as copper or aluminum.
Explanation:
from google
Why is it possible for an active metal like aluminum to be useful as a structural metal?
Answer:
Aluminum even after being an active metal is used as a structural metal due to its toughness, high strength, lightweight, and resistance to the process of corrosion. It is resistant to corrosion as its reactivity gets suppressed due to the formation of an aluminum oxide film which is protective in nature, on its surface. Passivation is the term for the formation of the protective coating.
Rust has the same properties as iron
True
False
Answer:
false
Explanation:
Most of the elements in the periodic table can be described as:
A. metalloids
B. halogens
c. non-metals
D. metals
The answer would be metals :)
Why are standard electrode potentials usually measured at 1.0 M electrolyte concentration?
Answer:
To avoid variation due to concentration
Explanation:
Hope this helps :)