Answer:
Explanation:
You realize that C2H5OH releases -1277.3kJ/mol. We need to convert this to the amount based on the question. We that 22.52g of C2H5OH = 0.48884 mol.
This means that it will release (-1277.3)(0.48884) = 624.40 KJ of heat will be released. Note the negative sign is not necessary here (I think) because it says how much is released and not the change in heat of the system so it should be positive.
corrected question: A chemist adds 135mL of a 0.21M zinc nitrate solution to a reaction flask. Calculate the mass in grams of zinc nitrate the chemist has added to the flask. Round your answer to significant digits.
Answer:
5.37g
Explanation:
0.21M means ; 0.21mol/dm³
1dm³=1L , so we can say 0.21mol/L
if 0.21mol of Zinc nitrate is contained in 1L of water
x will be contained in 135mL of water
x= 0.21*135*10³/1
=0.02835moles
number of moles= mass/ molar mass
mass= number of moles *molar mas
molar mass of Zn(NO₃)₂=189.36 g/mol
mass= 0.02835 *189.36
mass=5.37g
Answer:
A lower ph is always more acidic, due to the increased concentration of hydrogen ions in the solution/substance.
A ph of 3 is 100 times more acidic than a pH of 5, and this is due to the increments on the scale.
