Answer:
6.38
Explanation:
line up the decimals
it helps to add another 0 to 2.6 so that you can align them better
1
2.60
+ 3.78
= 6.38
8 + 0 = 8
6 + 7 = 13; write 3 and carry the one over above the 2 in 2.60
2 + 3 + 1 = 6
I tried my best to show it through text.
Answer:
1) 4Fe + 3O2 → 2Fe2O3
2) H2 + Cl2 → 2HCl
3) 2Ag + H2S → Ag2S + H2
4) CH4 + 2O2 → CO2 + 2H2O
5) 2HgO → 2Hg + O2
6) 2Co + 3H2O → Co2O3 + 3H2
Answer:
The answer to your question is V = 0.32 L
Explanation:
Data
Volume of NH₃ = ?
P = 3.2 atm
T = 23°C
mass of CaH₂ = 2.65 g
Balanced chemical reaction
6Ca + 2NH₃ ⇒ 3CaH₂ + Ca₃N₂
Process
1.- Convert the mass of CaH₂ to moles
-Calculate the molar mass of CaH₂
CaH₂ = 40 + 2 = 42 g
42 g ------------------ 1 mol
2.65 g -------------- x
x = (2.65 x 1)/42
x = 0.063 moles
2.- Calculate the moles of NH₃
2 moles of NH₃ --------------- 3 moles of CaH₂
x --------------- 0.063 moles
x = (0.063 x 2) / 3
x = 0.042 moles of NH₃
3.- Convert the °C to °K
Temperature = 23°C + 273
= 296°K
4.- Calculate the volume of NH₃
-Use the ideal gas law
PV = nRT
-Solve for V
V = nRT / P
-Substitution
V = (0.042)(0.082)(296) / 3.2
-Simplification
V = 1.019 / 3.2
-Result
V = 0.32 L
Answer:
* 
* 
* 
Explanation:
Hello,
In this case, for the mole fraction of methanol we use the formula:
Thus, we compute the moles of both water (molar mass 18 g/mol) and methanol (molar mass 32 g/mol):
Hence, mole fraction is:
Next, mass percent is:
And the molality, considering the mass of water in kg (0.185 kg):
Regards.
Answer:
54.1 % Ca, 43.2 % O, 2.7% H
Explanation:
Molecular formula for calcium hydroxide is Ca(OH)₂
As we don't have a mass of Ca(OH)₂ to find out the percentage composition, we consider that the question refers to 1 mol of compound.
1 mol of hydroxide weighs 74.08 g
1 mol of hydroxide has 1 mol of Ca, therefore 40.08 g are Ca
2 moles of O therefore 32g are O
2 moles of H therefore 2 g are H
Percentage composition is known as (Mass of element/Total mass) . 100
- (40.08 / 74.08) . 100 = 54.1 %
- (32 / 74.08) . 100 = 43.2 %
- (2 / 74.08) . 100 = 2.7%
