9 (a) Which of these means changing state from solid directly to gas?
A condensing
B freezing
C melting
D sublimating
(b) An object has a mass of 7.22 x 10^2 kg and a volume of 2.69 x 10^-3 m³ - Edexcel - GCSE Physics - Question 9 - 2023 - Paper 2
Question 9
9 (a) Which of these means changing state from solid directly to gas?
A condensing
B freezing
C melting
D sublimating
(b) An object has a mass of 7.22... show full transcript
Worked Solution & Example Answer:9 (a) Which of these means changing state from solid directly to gas?
A condensing
B freezing
C melting
D sublimating
(b) An object has a mass of 7.22 x 10^2 kg and a volume of 2.69 x 10^-3 m³ - Edexcel - GCSE Physics - Question 9 - 2023 - Paper 2
Step 1
Which of these means changing state from solid directly to gas?
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The correct answer is D) sublimating. This describes a change of state from solid to gas.
Step 2
Calculate the density, ρ, of the object.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To calculate the density, use the formula:
ρ=Vm
Substituting the values:
ρ=2.69×10−3 m37.22×102 kg
This gives: ρ=2680 kg/m3.
Step 3
State the unit.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The unit of density is kg/m³.
Step 4
Calculate the melting point of aluminium in kelvin.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To convert from Celsius to Kelvin, use the formula:
K=°C+273
Therefore:
K = 660 + 273 = 933 ext{ K}
$$.
Step 5
Describe the motion of particles in liquid aluminium (above 660 °C).
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
In liquid aluminium, the particles move freely and randomly. They have various speeds and can slide over one another. The kinetic energy of the particles is higher than in the solid state, allowing them to move around more easily.