Question:
<span>A sample of nitrogen gas had a volume of 500mL, a pressure in its closed container of 740 torr and a temperature of 25°c. what was the volume of gas when the temperature was changed to 50°c and the new pressure was 760 torr?
Answer:
Data Given:
V</span>₁ = 500 mL
P₁ = 740 torr
T₁ = 25 °C + 273 = 298 K
V₂ = ?
P₂ = 760 torr
T₂ = 50 °C + 273 = 323 K
Solution:
Let suppose the gas is acting Ideally, then According to Ideal Gas Equation,
P₁ V₁ / T₁ = P₂ V₂ / T₂
Solving for V₂,
V₂ = (P₁ V₁ T₂) ÷ (T₁ P₂)
Putting Values,
V₂ = (740 torr × 500 mL × 323 K) ÷ (298 K × 760 torr)
V₂ = 527.68 mL
What are the phrases to choose from?
The molarity of aqueous lithium bromide, LiBr solution is 0.2 M
We'll begin by calculating the number of mole of Pb(NO₃)₂ in the solution.
- Volume = 10 mL = 10 / 1000 = 0.01 L
- Molarity of Pb(NO₃)₂ = 0.250 M
- Mole of Pb(NO₃)₂ =?
Mole = Molarity x Volume
Mole of Pb(NO₃)₂ = 0.25 × 0.01
Mole of Pb(NO₃)₂ = 0.0025 mole
Next, we shall determine the mole of LiBr required to react with 0.0025 mole of Pb(NO₃)₂
Pb(NO₃)₂ + 2LiBr —> PbBr₂ + 2LiNO₃
From the balanced equation above,
1 mole of Pb(NO₃)₂ reacted with 2 mole of LiBr.
Therefore,
0.0025 mole of Pb(NO₃)₂ will react with = 2 × 0.0025 = 0.005 mole of LiBr
Finally, we shall determine the molarity of the LiBr solution
- Mole = 0.005 mole
- Volume = 25 mL = 25 / 1000 = 0.025 L
- Molarity of LiBr =?
Molarity = mole / Volume
Molarity of LiBr = 0.005 / 0.025
Molarity of LiBr = 0.2 M
Learn more about molarity: brainly.com/question/10103895
Answer:
The correct options are:
1) Pure chemical substance
2) Element.
Explanation:
each of the term is explained below:
1) <u>Mixture: </u> Since tungsten is an element in periodic table thus it is not a mixture.
2) False by definition of mixture.
3) false by definition of mixture.
4) <u>Solution:</u> Tungsten in a filament is in solid form hence solution is incorrect.
5) Since it is given in the question itself that the sample is pure hence option 'E' is correct as chemical substance is a pure substance that has a homogeneous composition and the sample in the question is given as pure.
6) <u>Compound:</u> By definition of compound it is formed by mixing 2 or more elements but since tungsten is an element that occurs independently in nature hence it is not a compound.
7) Tungsten is a element in the periodic table with atomic number 74.
Answer:
the molecules of water contracts when it is frozen