Answer:
Aluminium atoms = 4.13 *10^22 aluminium atoms
The correct answer is E
Explanation:
Step 1: Data given
Mass of Al2O3 = 3.50 grams
Molar mass of Al2O3 = 101.96 g/mol
Number of Avogadro = 6.022 * 10^23 /mol
Step 2: Calculate moles Al2O3
Moles Al2O3 = mass Al2O3 / molar mass Al2O3
Moles Al2O3 = 3.50 grams / 101.96 g/mol
Moles Al2O3 = 0.0343 moles
Step 3: Calculate moles Aluminium
In 1 mol Al2O3 we have 2 moles Al
in 0.0343 moles Al2O3 we have 2*0.0343 = 0.0686 moles Al
Step 4: Calculate aluminium atoms
Aluminium atoms = moles aluminium * Number of Avogadro
Aluminium atoms = 0.0686 * 6.022 * 10^23
Aluminium atoms = 4.13 *10^22 aluminium atoms
The correct answer is E
Answer:
The correct answer is "32%".
Explanation:
The given values:
Weight of H,
= 4.9 g
Weight of sample,
= 15.8 g
Now,
The weight percentage of C will be:
= 
By substituting the values, we get
= 
= 
Answer:
Explanation:
idk why all u guys like trump who do.. hes just a big pain in the a*s.
Answer:
The fraction of energy used to increase the internal energy of the gas is 0.715
Explanation:
Step 1: Data given
Cv for nitrogen gas = 20.8 J/K*mol
Cp for nitrogen gas = 29.1 J/K*mol
Step 2:
At a constant volume, all the heat will increase the internal energy of the gas.
At constant pressure, the gas expands and does work., if the volume changes.
Cp= Cv + R
⇒The value needed to change the internal energy is shown by Cv
⇒The work is given by Cp
To find what fraction of the energy is used to increase the internal energy of the gas, we have to calculate the value of Cv/Cp
Cv/Cp = 20.8 J/K*mol / 29.1 J/K*mol
Cv/Cp = 0.715
The fraction of energy used to increase the internal energy of the gas is 0.715
Answer:
= 12 mL H202
Explanation:
Given that, the concentration of H2O2 is given antiseptic = 3.0 % v/v
It implies that, 3ml H2O2 is present in 100 ml of solution.
Therefore, to calculate the amount of H202 in 400.0 mL bottle of solution;
we have;
(3.0 mL/ 100 mL) × 400 mL
= 12 mL H202
