Hey There!
At neutralisation moles of H⁺ from HCl = moles of OH⁻ from Ca(OH)2 so :
0.204 * 42.8 / 1000 => 0.0087312 moles
Moles of Ca(OH)2 :
2 HCl + Ca(OH)2 = CaCl2 + 2 H2O
0.0087312 / 2 => 0.0043656 moles ( since each Ca(OH)2 ives 2 OH⁻ ions )
Therefore:
Molar mass Ca(OH)2 = 74.1 g/mol
mass = moles of Ca(OH)2 * molar mass
mass = 0.0043656 * 74.1
mass = 0.32 g of Ca(OH)2
Hope that helps!
There are many different types of apples i dont EXACTLY know why but however there are some eople that can only have a certain type of apple
Answer:
- <em>(B.) The pH of a buffer solution is determined by the ratio of the concentration of conjugate base to the concentration of strong acid.</em>
- <em>(C.) A buffer is generally made up of a weak acid and its conjugate base. </em>
- <em>(D.) The pH of a buffer solution does not change significantly when any amount of a strong acid is added.</em>
Explanation:
A buffer is solution which resists change in pH upon addition of either acids or bases.
The pH of a buffer is calculated by the ratio of the concentration of base to concentration of acid. The weak acid and conjugate base have a Ka similar to the pH desired.
Answer:
H2 > N2 > Ar > CO2
Explanation:
Graham's law explains why some gases efuse faster than others. This is due to the difference i their molar mass. Generally; The rate of effusion of gaseous substances is inversely proportional to the square rot of its molar mass.
This means gases with low molar masses would have higher efusion rate compared to gases with higher molar masses.
So now we just need to compare the molar masses of the various gases;
Ar - 39.95
CO2 - 44.01
H2 - 2
N2 - 28.01
To obtain the order in increasing rate, we have to order the gases in decreasing molar mass. This order of increasing rate is given as;
H2 > N2 > Ar > CO2
Answer:
3.75 g.
Explanation:
<em>mass percent is the ratio of the mass of the solute to the mass of the solution multiplied by 100.</em>
<em />
<em>mass % = (mass of solute/mass of solution) x 100.</em>
<em></em>
mass of calcium nitrite = ??? g,
mass of the solution = 25.0 g.
∴ mass % = (mass of solute/mass of solution) x 100
<em></em>
<em>∴ mass of solute (calcium nitrite) = (mass %)(mass of solution)/100</em> = (15.0 %)(25.0 g)/100 = <em>3.75 g.</em>
