Best Answer:<span> </span><span>Sorry its kind of hard to explain, you just need to study hesslaw, practice makes perfect, keep studying!
A. REACTION 2 IS MULTIPLIED BY 3 (HESS LAW)
ΔH2= -6129 j
B. IF REACTION IS REVERSED YOU FLIP THE SIGN OF ΔH
ΔH = 92.3 kJ
C. KIND OF HARD TO EXPLAIN, BUT I CAN TRY AND SHOW YOU
EQUATION 1 (FLIP) CH4 --> C + H2
EQUATION 4 (FLIP AND MULTIPLY BY 2) H2O(g) --> H2O(l)
ΔH = -890.7</span>
Hello,
You balanced the equation and then you have to set up what is called a psychometric equation for each reactant so that you get the same unit for each in order to compare the two. so for (calcium hydroxide) = 78.5 g ÷ (40.1 + 32 + 2) = 1.0593 mol * Note: I just broke it down in my own science way..u can just get the molar mass of calcium hydroxide which is approx 74 g/mol
Hope this helps
<u>Given:</u>
# Molecules of NaOH = 1.50 * 10²³
<u>To determine:</u>
The # moles of NaOH present in the given molecules
<u>Explanation:</u>
By definition:
1 mole of NaOH corresponds to Avogadro's number i.e. 6.023*10²³ molecules
Therefore the moles of NaOH corresponding to the given molecules would be = 1.50*10²³ molecules NaOH * 1 mole NaOH/6.023*10²³ molecules NaOH
= 0.249 moles
Ans: 0.249 moles of NaOH