Answer:
Q = 1.5 kJ
Explanation:
It is given that,
The specific heat for aluminum is 0.900 J/g°C
Mass of sample, m = 3.8 g
Initial temperature,
Final temperature,
We need to find the heat released. The amount of heat released is given by the formula:
or
So, the correct option is (A) i.e. 1.5 kJ.
1 moL of a substance is equal to 6.02 x 10^23 atoms or particles , it true statement. This number is known as Avogadro number.
Answer:
all pure substance are molecules
Answer:
0.570 L
Explanation:
Given:
Concentration of the HCl solution = 0.750 M
Mass of NaCl in the reaction = 25.0
Number of moles of NaCl in the reaction = Mass of NaCl / Molar mass of NaCl
also,
Molar mass of NaCl = 22.98 + 35.45 = 58.43 grams
thus,
Number of moles of NaCl in the reaction = 25 / 58.43 = 0.4278 moles
now,
1 mol of NaCl reacts to form 1 mol of HCl
thus,
0.4278 moles of NaCl reacts to form 0.4278 mol of HCl
also,
Concentration = Moles / volume of solution
0.750 = 0.4278 / volume of solution
or
volume of solution = 0.570 L