-2.5089 kJ is the amount of heat is released by the combustion of the naphthalene.
<h3>How we calculate the released heat?</h3>
Released amount of heat is calculated by using the below formula:
Q = -mcΔT, where
m = mass of naphthalene = 0.25g
c = specific heat of calorimeter = 4.13 kJ/°C
ΔT = change in temperature = 26.43°C - 24°C = 2.43°C
Putting all these values in the above equation, we get
Q = - (0.25 × 4.13 × 2.43) = - 2.5089 kJ
Hence, - 2.5089 kJ heat is released.
To know more about released heat, visit the below link:
brainly.com/question/13439286
Answer:
20 g of CO₂ have 5.47x10²³ oxygen atoms
Explanation:
1 mol of CO₂ has 1 mol of C and 2 moles of O.
Mass / Molar mass = Moles
20 g / 44 g/m = 0.454 moles
In 1 mol we find 2 moles of O
In 0.454 moles of CO₂, we will find ( 0.454 .2) = 0.909 moles
1 mol has _____ 6.02x10²³ atoms
0.909 moles have (0.909 . 6.02x10²³) = 5.47x10²³ atoms
Answer:
A) Charging by contact
Explanation:
Transfer of heat by direct contact, Heat energy is conducted from the hotter medium to the cooler medium
The molar mass of methanol is 12.01 + 4.04 + 16 = 32.05 g/mol
230.0 g of methanol / 32.05 g/mol = 7.176 mol methanol
The heat of combustion of methanol (CH3OH or CH4O) is -715.0 kJ/mol. (Negative sign means the energy is released)
Multiplying 7.176 mol by -715.0 kJ/mol gives -5,131 kJ.
