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.)
Answer:
The temperature of the gas is 876.69 Kelvin
Explanation:
Ideal gases are a simplification of real gases that is done to study them more easily. It is considered to be formed by point particles, do not interact with each other and move randomly. It is also considered that the molecules of an ideal gas, in themselves, do not occupy any volume.
The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:
P*V = n*R*T
where P is the gas pressure, V is the volume that occupies, T is its temperature, R is the ideal gas constant, and n is the number of moles of the gas.
In this case:
- P= 470 mmHg
- V= 570 mL= 0.570 L
- n= 0.216 g= 0.0049 moles (being the molar mass of carbon dioxide is 44 g/mole)
- R= 62.36367

Replacing:
470 mmHg*0.570 L= 0.0049 moles* 62.36367
*T
Solving:

T= 876.69 K
<em><u>The temperature of the gas is 876.69 Kelvin</u></em>
Answer:
P1V1= P2V2
Explanation:
Inverse relationship
V2 = V1 X P1/P2
V2= 14.3 L x 45.0 mm Hg/63.0 mmHg= 8.99
Number of moles : n₂ = 1.775 moles
<h3>Further explanation</h3>
Given
Moles = n₁ = 1.4
Volume = V₁=22.4 L
V₂=28.4 L
Required
Moles-n₂
Solution
Avogadro's hypothesis, at the same temperature and pressure, the ratio of gas volume will be equal to the ratio of gas moles
The ratio of gas volume will be equal to the ratio of gas moles

Input the values :
n₂ = (V₂ x n₁)/V₁
n₂ = (28.4 x 1.4)/22.4
n₂ = 1.775 moles
The changes that are common between sauce burning on a stove, and jewelry tarnishing, which is a chemical change.
How to define chemical and physical changes?
Chemical Change-
Any alteration that produces new chemical substances with distinct properties is considered a chemical change. Chemical reactions involve the rearrangement and recombination of elements and compounds to create new substances. Examples of chemical changes are listed below:
- Burning
- Digestion
- chemicals changing colors
- Tarnishing
- compost rotting
Physical Change-
A substance is not destroyed or transformed into something new by physical changes. A substance can undergo physical changes that alter its shape, size, or phase. The constituents of an element or compound do not change during a physical change. Examples of physical changes are listed below:
- Boiling water
- Chopping, Cutting, Carving
- Evaporation
- Freezing, Melting, Condensation
To know more about chemical and physical changes, visit the given link:
brainly.com/question/20628019
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