Answer:
The correct answer is 596.5 kJ.
Explanation:
The mass of ethanol or C2H5OH mentioned in the question is 20 gm.
The molar mass of ethanol is 46 g/mol.
The moles of the compound can be determined by using the formula,
n = weight of the compound/molar mass
= 20/46 = 0.435 moles
It is mentioned in the question that standard heat of combustion of ethanol is 1372 kJ/mole, that is, one mole of ethanol is producing 1372 kilojoules of energy at the time of combustion.
Therefore, the energy liberated by completely burning the 20 grams of ethanol is 0.435*1372 = 596.5 kJ.
Hmm, welll I think it’s heterogeneous
Answer: I believe/don't believe that smoking increases the risk of lung cancer because...(add your three reasons if writing an essay)
Explanation:
Since a hypothesis is basically your inference, these hypothesis can vary.
:) Hope this helped
when the half-life is the amount of time which the radioactive isotopes need to
be in half.
So when w start with 32 g of unobtanium 53 so :
1- after 20 sec the number of grams remain = 32/2
= 16 g
2- and after 40 sec the number of grams remain
16 g will cut in half:
= 16 / 2
= 8 g
3- and after 60 sec the number of grams remain
8 g will cut in half:
= 8g /2
= 4 g
4- and after 80 sec the number of grams remain
4 g will cut in half:
= 4 g /2
= 2 g
5-after 100 sec the number of grams remain
2 g will cut in half :
= 2g /2
= 0 g
after 100 sec there are no grams remain
