Answer: 40.68 kPa
Explanation:
Given that,
Original volume of gas V1 = 21.7 mL
Original pressure of gas P1 = 98.8 kPa
New volume of gas V2 = 52.7 mL
New pressure of gas P2 = ?
Since pressure and volume are given while temperature is constant, apply the formula for Boyle's law
P1V1 = P2V2
98.8 kPa x 21.7 mL = P2 x 52.7L
2143.96 kPa L = 52.7 L x P2
P2 = 2143.96 kPa L / 52.7 L
P2 = 40.68 kPa
Thus, the new pressure of the gas is 40.68 kPa.
Answer:
6. 7870 kg/m³ (3 s.f.)
7. 33.4 g (3 s.f.)
8. 12600 kg/m³ (3 s.f.)
Explanation:
6. The SI unit for density is kg/m³. Thus convert the mass to Kg and volume to m³ first.
1 kg= 1000g
1m³= 1 ×10⁶ cm³
Mass of iron bar
= 64.2g
= 64.2 ÷1000 kg
= 0.0642 kg
Volume of iron bar
= 8.16 cm³
= 8.16 ÷ 10⁶


Density of iron bar

= 7870 kg/m³ (3 s.f.)
7.

Mass
= 1.16 ×28.8
= 33.408 g
= 33.4 g (3 s.f.)
8. Volume of brick
= 12 cm³

Mass of brick
= 151 g
= 151 ÷ 1000 kg
= 0.151 kg
Density of brick
= mass ÷ volume

(3 s.f.)
The size of an atom is roughly 10^-10 metres
10^-10 • 100,000,000 = 0.01 metres
Since 1 metre = 100 centimetre
0.01 x 100 = 1 centimetre
There’s your answer
Answer: -
3.151 M
Explanation: -
Let the volume of the solution be 1000 mL.
At 25.0 °C, Density = 1.260 g/ mL
Mass of the solution = Density x volume
= 1.260 g / mL x 1000 mL
= 1260 g
At 25.0 °C, the molarity = 3.179 M
Number of moles present per 1000 mL = 3.179 mol
Strength of the solution in g / mol
= 1260 g / 3.179 mol = 396.35 g / mol (at 25.0 °C)
Now at 50.0 °C
The density is 1.249 g/ mL
Mass of the solution = density x volume = 1.249 g / mL x 1000 mL
= 1249 g.
Number of moles present in 1249 g = Mass of the solution / Strength in g /mol
= 
= 3.151 moles.
So 3.151 moles is present in 1000 mL at 50.0 °C
Molarity at 50.0 °C = 3.151 M
Mixture is a combination of two or more substances. The components of the mixture are not chemically reacted and can be separated using physical means.
compound is a combination of two or more substances that are chemically reacted or bound together. The components of the compound cannot be separated except by chemical reactions.
Answer:
<span>(4) consist of two or more substances</span>