Answer:
9.1 KJ
Explanation:
First we must find the number of moles of HBr involved;
number of moles of HBr= mass of HBr/ molar mass of HBr
But molar mass of HBr= 80.91 g/mol
Given mass of HBr from the question= 20.1g
Hence;
Number of moles of HBr= 20.1 g/80.91g
Number of moles of HBr= 0.25 moles of HBr
If 2 moles of HBr has a heat of formation of 72.80KJ
Then 0.25 moles of HBr will have a heat of formation of 0.25× 72.80/2= 9.1 KJ
Therefore; 20.1 g of HBr will have a heat of formation of 9.1 KJ
Answer:
0.0125mol
Explanation:
Molarity (M) = number of moles (n) ÷ volume (V)
n = Molarity × Volume
According to this question, a 0.05M solution contains 250 mL of NaOH. The volume in litres is as follows:
1000mL = 1L
250mL = 250/1000
= 0.250L
n = 0.05 × 0.250
n = 0.0125
The number of moles of NaOH is 0.0125mol.
Answer:
Mass of carbon dioxide = 7.48 g
Explanation:
Given data:
Mass of lithium carbonate = 12.5 g
Mass of carbon dioxide produced = ?
Solution:
Chemical equation:
Li₂CO₃ → Li₂O + CO₂
Number of moles of Li₂CO₃:
Number of moles = mass/ molar mass
Number of moles = 12.5 g /73.89 g/mol
Number of moles = 0.17 mol
Now we will compare the moles of Li₂CO₃ with CO₂.
Li₂CO₃ : CO₂
1 : 1
0.17 : 0.17
Mass of carbon dioxide:
Mass of carbon dioxide = number of moles × molar mass
Mass of carbon dioxide = 0.17 mol × 44 g/mol
Mass of carbon dioxide = 7.48 g
A...because both of them(carbon and oxygen)are nonmetal
The answer to this question would be: ammonia
Chemical decomposition is the breakdown of a compound into smaller compound or element. In this question, the Sodium(Na), Argon (Ar) and Sulfur(S) is elements, not compounds.
An element should not breakable since it was the simplest form.
Ammonia(NH3) is a compound so it should be able to be decomposed.
