Answer:
The molar mass of Ca(OH)2 is 74.092 g/mol
Explanation:
First your going to find the atomic mass of each element on the periodic table.
Ca(Calcium) = 40.078
O(Oxygen) = 15.999
H(Hydrogen) = 1.008
Then we can create the equation:
40.078 + (15.999 + 1.008) × 2
40.078 + (17.007) × 2
40.078 + 34.014
= 74.092 g/mol
Answer is: 162 g of beryllium.
Chemical reaction: Be + 2H₂O → Be(OH)₂ + H₂.
m(H₂) = 36,0 g.
m(Be) = ?
n(H₂) = m(H₂) ÷ M(H₂)
n(H₂) = 36,0 g ÷ 2 g/mol = 18 mol.
from reaction: n(Be) : n(H₂) = 1 : 1.
n(Be) = n(H₂) = 18 mol.
m(Be) = n(Be) · M(Be).
n(Be) = 18 mol · 9 g/mol = 162 g.
Answer:
1.67 atm.
Explanation:
- We can use the general law of ideal gas: PV = nRT.
where, P is the pressure of the gas in atm (P = ??? atm).
V is the volume of the gas in L (V = 5.0 L).
n is the no. of moles of the gas in mol (n = 0.5 mol).
R is the general gas constant (R = 0.0821 L.atm/mol.K),
T is the temperature of the gas in K (T = 203 K).
∴ P = nRT/V = (0.5 mol)(0.0821 L.atm/mol.K)(203 K)/(5.0 L) = 1.67 atm.
Answer:
The ideal gas equation
Explanation:
The ideal gas equation is derived from the combination of three gas laws:
- Boyle's law
- Charles's law
- Avogadro's law.
The ideal gas law is expressed mathematically as: PV=nRT where:
P is pressure
V is volume
n is the number of moles
R is the ideal gas law
T is temperature.
To obtain the combined gas law, we assume that n=1 and this gives:
= R
Therefore:
= 
I think the reaction involved here is a redox reaction in acidic conditions. To balance this type of reaction, we do as follows:
Balance the O atoms in each side by adding H2O on either side.
Balance H atoms in each side by adding H+.
Balance the charges by adding electrons.
Hope this helps.
