Explanation:
Given
The enthalpy of formation of RbF (s) is –557.7kJ/mol
The standard enthalpy of formation of RbF (aq, 1 m) is –583.8 kJ/mol
The enthalpy of solution of RbF = Enthalpy of RbF (aq) - Enthalpy of formation of RbF (s)
= -583.8 - (-557.7) kJ/mol
= -26.1 kJ/mol
The enthalpy is negative which means that the temperature will rise when RbF is dissolved.
Answer:
True
Explanation:
magnesium and copper react with dilute acids to make salts and hydrogen gas
Balanced chemical reaction: 2K(s) + 2H₂O(l) → 2KOH(aq) + H₂(g).
KOH is inorganic compound p<span>otassium hydroxide, a strong base.
H</span>₂ is hydrogen gas.
In balanced chemical reaction number of atoms on both side of chemical reaction must be same. There are two potassium atoms, four hydrogen atoms and two oxygen atoms on both side of reaction.
1L = 33.814 oz
xL = 2.75 oz
so it's a proportion
1L / 33.814 oz = xL / 2.75
solve for x
(1/33.814) * 2.75 = 0.0813272609 on your calculator, but it's not the answer.
the number in your problem, 2.75 oz, has 3 significant figures. so you can only round this number to 3 significant figures too.
your equipment isn't accurate enough to give a reading to 10 significant figures if that makes sense. you have to give the answer in terms of the term you use with the lowest significant figures.
so with 3 significant figures,
0.0813272609 rounds to
0.0813 L
