Answer: C) 0.020 m
Explanation:
Molality of a solution is defined as the number of moles of solute dissolved per kg of the solvent.
where,
n = moles of solute
= weight of solvent in g
Mole fraction of is = i.e. moles of is present in 1 mole of solution.
Moles of solute =
moles of solvent (water) = 1 - = 0.99
weight of solvent =
Molality =
Thus approximate molality of in this solution is 0.020 m
Answer:
E) C₂H₄(g) + H₂(g) ⇒ C₂H₆(g)
Explanation:
Which ONE of the following is an oxidation–reduction reaction?
A) PbCO₃(s) + 2 HNO₃(aq) ⇒ Pb(NO₃)₂(aq) + CO₂(g) + H₂O(l). NO. All the elements keep the same oxidation numbers.
B) Na₂O(s) + H₂O(l) ⇒ 2 NaOH(aq). NO. All the elements keep the same oxidation numbers.
C) SO₃(g) + H₂O(l) ⇒ H₂SO₄(aq). NO. All the elements keep the same oxidation numbers.
D) CO₂(g) + H₂O(l) ⇒ H₂CO₃(aq). NO. All the elements keep the same oxidation numbers.
E) C₂H₄(g) + H₂(g) ⇒ C₂H₆(g). YES. <u>C is reduced</u> and <u>H is oxidized</u>.
The balloon's volume at 35°C : V₂=31.01 L
<h3>Further explanation</h3>
Given
T₁ = 25°C+273 = 298 K
V₁ = 30 L
T₂ = 35 °C + 273 = 308 K
Required
The new volume (V₂)
Solution
Charles's Law
When the gas pressure is kept constant, the gas volume is proportional to the temperature
Input the value :
V₂=(V₁.T₂)/T₁
V₂=(30 x 308)/298
V₂=31.01 L