D, the change from a liquid to solid is called freezing.
Answer: His cells use oxygen to break down food molecules to release energy
Explanation:
Answer:The process is known as sublimation
Explanation:
Sublimation is a process wherby solid substances are changed into gaseous state
Answer:
Q1. a) 4Al + 3O₂ ➟ 2Al₂O₃
b) 7.4 moles
c) 11.1 moles
Explanation:
To balance an equation, ensure that the total number of atoms of each element on both sides are equal.
Al + O₂ ➟ Al₂O₃
On the left side of the arrow, you would find the reactants while the product(s) is found on the left hand side.
<u>Reactants</u>
Al atoms: 1
O atoms: 2
<u>Product</u>
Al atoms: 2
O atoms: 3
After balancing,
4Al + 3O₂ ➟ 2Al₂O₃
We have 4 Al atoms and 6 O atoms on both sides.
b) The balanced equation tells us the mole ratio of Al to Al₂O₃.
Al: Al₂O₃
= 4: 2 (÷2 throughout)
= 2: 1
This means that for every 1 mole of Al₂O₃, 2 moles of Al is needed.
Since we need 3.7 moles of Al₂O₃,
number of moles of Al needed
= 2×3.7
= 7.4
c) 4Al + 3O₂ ➟ 2Al₂O₃
For every 4 moles of Al, 3 moles of O are needed.
For each mole of Al,
number of moles of O needed
= 3÷4
= 0.75
For 14.8 moles of Al,
number of moles of O required
= 0.75 ×14.8
= 11.1
Answer :
The substance is in the gas phase only in region → 5
The substance is in both the liquid and the solid phase in region → 2
The substance is in only the liquid phase in region → 3
The melting point is the temperature at region → 2
The boiling point is the temperature at region → 4
Explanation :
Six phases of substance:
- Melting or fusion : In this process the phase changes from solid state to liquid state at constant temperature.
- Freezing : In this process the phase changes from liquid state to solid state at constant temperature.
- Evaporation : In this process the phase changes from liquid state to gaseous state at constant temperature.
- Condensation : In this process the phase changes from gaseous state to liquid state at constant temperature.
- Sublimation : In this process the phase changes from solid state to gaseous state without passing through the liquid state at constant temperature.
- Deposition : In this process the phase changes from gaseous state to solid state without passing through the liquid state at constant temperature.
