Formula: % by mass = (mass of solute / mass of solution] *100
Data:
mass of solution = 80.85 g
% by mass = 22.4%
Unknown = mass of solute
Solution
% by mass = (mass of solute / mass of solution] *100 = >
mass of solute = % by mass * mass of solution / 100
mass of solute = 22.4 * 80.85 / 100 = 18.11 g
Answer: 18.11 g
Answer:
c. -1020.9 kJ
Explanation:
4Fe (s) + 3 O₂ (g) --> 2 Fe₂O₃(s) ΔH = -826.0 kJ/mol.
atomic weight of iron = 56
69.03 g = 69.03 / 56
= 1.23268 moles
Heat released by 1.23268 moles
= 1.23268 x 826.0
= -1020.9 kJ .
Mario places 10 mL of water in a test tube and heats the liquid over a Bunsen burner for 2 minutes. After removing the test tube from the Bunsen burner, there are 6 mL of water left in the test tube. This experiment is a good example of a <span>physical change involving phase changes. </span>
Answer: The expression for equilibrium constant is ![\frac{[NH_3]^2}{[H_2]^3[N_2]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BNH_3%5D%5E2%7D%7B%5BH_2%5D%5E3%5BN_2%5D%7D)
Explanation: Equilibrium constant is the expression which relates the concentration of products and reactants preset at equilibrium at constant temperature. It is represented as 
For a general reaction:
The equilibrium constant is written as:
![k_c=\frac{[C]^c[D]^d}{[A]^a[B]^b}](https://tex.z-dn.net/?f=k_c%3D%5Cfrac%7B%5BC%5D%5Ec%5BD%5D%5Ed%7D%7B%5BA%5D%5Ea%5BB%5D%5Eb%7D)
Chemical reaction for the formation of ammonia is:
Expression for is:
![k_c=\frac{[NH_3]^2}{[H_2]^3[N_2]}](https://tex.z-dn.net/?f=k_c%3D%5Cfrac%7B%5BNH_3%5D%5E2%7D%7B%5BH_2%5D%5E3%5BN_2%5D%7D)
![1.6\times 10^2=\frac{[NH_3]^2}{[H_2]^3[N_2]}](https://tex.z-dn.net/?f=1.6%5Ctimes%2010%5E2%3D%5Cfrac%7B%5BNH_3%5D%5E2%7D%7B%5BH_2%5D%5E3%5BN_2%5D%7D)
Answer:
a. Work
Explanation:
If you apply a force over a given distance - you have done work. Work = Change in Energy. If an object's kinetic energy or gravitational potential energy changes, then work is done. The force can act in the same direction of motion.
