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.
Answer:
1 1
5 2
6 1
8 3
10 3
6 3
9 3
13 3
Explanation:
First of you add the subscripts (the little numbers after the letters) and multiply the big numbers before the letters together to get the number of atoms
For Example:
O= 1 atom
Si{2}= 2 atoms
Mg{5}C{6}= 11 atoms
3Na{2}= 6 atoms
O(SiNa){2}= OSi{2}Na{2}= 5 atoms
Each Capital letter is a new Element
For Example:
O = 1 Element
NaSi = 2 Elements
Answer:
dry
Explanation:
it will dry the hydrogen chloride to the ammonia
Answer:
8×10^(-3) mol/L
Explanation:
The formula for finding the hydrogen ion concentration is...
[H⁺] = 10^-ph
[H⁺] = 10^(-2.1)
[H⁺] = 0.00794...mol/L = 8×10^(-3) mol/L
The answer is to 1 significant digit because the pH has one decimal place.
