Answer:
0.134 moles of H₂ can be formed if a 3.25g sample of Mg reacts with excess HCl
Explanation:
The balanced reaction is:
Mg + 2 HCl → MgCl₂ + H₂
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles react:
- Mg: 1 mole
- HCl: 2 moles
- MgCl₂: 1 mole
- H₂: 1 mole
Being:
- Mg: 24. 31 g/mole
- H: 1 g/mole
- Cl: 35.45 g/mole
the molar mass of the compounds participating in the reaction is:
- Mg: 24.31 g/mole
- HCl: 1 g/mole + 35.45 g/mole= 36.45 g/mole
- MgCl₂: 24.31 g/mole + 2*35.45 g/mole= 95.21 g/mole
- H₂: 2*1 g/mole= 2 g/mole
Then, by stoichiometry of the reaction, the following quantities of mass participate in the reaction:
- Mg: 1 mole* 24.31 g/mole= 24.31 g
- HCl: 2 moles* 36.45 g/mole= 72.9 g
- MgCl₂: 1 mole* 95.21 g/mole= 95.21 g
- H₂: 1 mole* 2 g/mole= 2 g
Then you can apply the following rule of three: if by stoichiometry 24.31 grams of Mg form 1 mole of H₂, 3.25 grams of Mg how many moles of H₂ will they form?
moles of H₂= 0.134
<u><em>0.134 moles of H₂ can be formed if a 3.25g sample of Mg reacts with excess HCl</em></u>
Answer:
To move? I think that's right
Answer:
29.88 g/mol
Explanation:
Lithium has molar mass of 6.94 g/mol and oxygen has weight of 16 g/mol. Since there are 2 lithium, Li would be 13.88 g/mol and 13.88+16=29.88 g/mol
Ans: pH = 9
<u>Given:</u>
Concentration of H+ ions [H+] = 1.0*10⁻⁹ M
<u>To determine:</u>
The pH of the above solution
<u>Explanation:</u>
pH = -log[H+]
pH = -log(1.0*10⁻⁹) = 9
2.3 dL = .23 liters. d=deci=10^-1 so you move the decimal place back once.
It's D because micro is 10^-6 (move the decimal place back 6 times) 230,000x10^-6=.23 liters or 2.3 dL.