I used to know this. I don't really remember but is used to know it. Im in 6th grade now
Answer:
= 25.05°C
Explanation:
Given:
the value of ΔHcomb (heat of combustion) for dimethylphthalate (C10H10O4) is = 4685 kJ/mol.
mass = 0.905g of dimethylphthalate
molar mass = 194.18g dimethylphthalate
number of moles of dimethylphthalate = ???
= 21.5°C
= 6.15 kJ/°C
= ???
since we have our molar mass and mass of dimethylphthalate ;we can determine the number of moles as;
0.905g of dimethylphthalate × 
number of moles of dimethylphthalate = 0.000466 moles
Heat released = moles of dimethylphthalate × heat of combustion
= 0.000466 moles × 4685 kJ
= 21.84 kJ
∴ Heat absorbed by the calorimeter =

21.84 kJ =6.15 kJ/°C 
21.84 KJ = 
21.84 KJ =
- 132.225 kJ
21.84 KJ + 132.225 kJ = 
154.065 kJ = 
= 
=25.05°C
Answer:
500
Explanation:
from the average and if yoy multiple and then add your % and x you would get 500 to 600
The density of hydrogen : ρ = 0.0892 g/L
<h3>Further explanation</h3>
Given
mass of Hydrogen : 0.446 g
Volume = 5 L
Required
The density
Solution
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
The unit of density can be expressed in g/cm³, kg/m³, or g/L
Density formula:

Input the value :
ρ = m : V
ρ = 0.446 g : 5 L
ρ = 0.0892 g/L