Answer:
236.8 g
Explanation:
From the reaction equation;
CaC2 + 2H2O(I) --------> C2H2(g) + Ca(OH)2(aq)
Since;
1 mole of CaC2 yields 1 mole of Ca(OH)2
It follows that 3.20 moles of CaC2 also yields 3.2 moles of Ca(OH)2
Mass of Ca(OH)2 = number of moles * molar mass
molar mass of Ca(OH)2 = 74 g/mol
Mass of Ca(OH)2 = 3.20 moles * 74 g/mol =
Mass of Ca(OH)2 = 236.8 g
Answer:
0.6 moles of Fe
Explanation:
Given data:
Number of atoms of Fe = 3.612×10²³
Number of moles = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
From atoms to mole:
3.612×10²³ atoms of Fe × 1 mole / 6.022 × 10²³ atoms
0.6 moles of Fe
B
Explanation:
I rember when I learned this in 3rd grade
Answer:
-1151.5 J
Explanation:
Given that:
The supplies energy = 245 L
The energy used in the expansion of gas = Pressure ×ΔV (change in volume)
At standard conditions;
Pressure = 105 × 10³ Pa
energy used in the expansion = 105 × 10³ Pa × (38.6 - 25.3)L
= 1396.5 J
Thus, the change in the energy of gas = 245 - 1396.5 J
= -1151.5 J
Hence, we can conclude that the gas has lost its own energy in the process of expansion.
Answer:
V₂ = 116126.75 cm³
Explanation:
Given data:
Radius of balloon = 15 cm
Initial pressure = 2 atm
Initial temperature = 35 °C (35 +273 = 308K)
Final temperature = -20°C (-20+273 = 253 K)
Final pressure = 0.3 atm
Final volume = ?
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
Initial volume of balloon:
V = 4/3πr³
V = 4/3×22/7×(15cm)³
V = 14137.17 cm³
V₂ = P₁V₁ T₂/ T₁ P₂
V₂ = 2 atm × 14137.17 cm³ × 253 K / 308 K × 0.3 atm
V₂ = 7153408.02 atm .cm³. K / 61.6 K.atm
V₂ = 116126.75 cm³
