Answer:
t = 5.7634 s
Explanation:
- A → Pdts
- - rA = K (CA)∧α = - δCA/δt
∴ T = 400°C
∴ α = 1 ....first-order
∴ CAo = 0.950 M
∴ CA = 0.300 M
⇒ t = ?
⇒ - δCA/δt = K*CA
⇒ - ∫δCA/CA = K*∫δt
⇒ Ln (CAo/CA) = K*t
⇒ t = Ln(CAo/CA) / K
⇒ t = (Ln(0.950/0.300)) / (0.200 s-1)
⇒ t = 1.1527 / 0.200 s-1
⇒ t = 5.7634 s
A. is decomposition so HCL = H2 + Cl2
not balanced cause hcl needs 2
2HCL = H2 + Cl2
balanced
b. Br2 + Al-i = AlBr3 + I2 single rep.
not balanced since br need 3 so watch carefully cause many changes needed
3Br2 + Al-i = AlBr3 + I2 not right is unbalanced so make it 2
3Br2 + Al-i = 2AlBr3 + I2 now left Al is unbal. so make 2 there
3Br2 + 2Ali = 2AlBr3 + I2
Balanced
C. Na + S = Na2S synthesis reaction is not bal. left Na needs 2
2Na + S = Na2S balanced.
Answer is: the molar mass od sodium carbonate (Na₂CO₃) is 106.0 g/mol.
M(Na₂CO₃) = 2 · Ar(Na) + Ar(C) + 3 · Ar(O).
M(Na₂CO₃) = 2 · 23 + 12 + 3 · 16 · g/mol.
M(Na₂CO₃) = 46 + 12 + 48 · g/mol.
M(Na₂CO₃) = 106 g/mol; molar mass of sodium carbonate.
Ar is relative atomic mass (the ratio of the average mass of atoms of a chemical element to one unified atomic mass unit) of an element.
