Answer:
18- H
19- D
20-G
21-A
(i think these are the answers)
Explanation:
<h3>
Answer:</h3>
0.002 moles
<h3>
Explanation:</h3>
Concept tested: Molarity
We are given;
- Volume of HCl as 20 ml or 0.02 L
- Molarity of HCl solution as 0.10 M
We are required to calculate the number of moles of HCl
What is molarity?
- Molarity is the concentration of a solution in moles per liter
How is it calculated?
- It calculated by dividing number of moles by volume;
- Molarity = Number of moles ÷ Volume
To calculate the number of moles we rearrange the formula;
Moles = Molarity × Volume
In this case;
Moles of HCl = 0.10 M × 0.02 L
= 0.002 moles
Therefore, the number of moles of HCl is 0.002 moles
Answer:
B. all the above no wrong answer
Answer:
Molecules are speeding up during boiling
Explanation:
According to the kinetic theory of matter, matter exists in three states; solid, liquid and gas. In the solid state, the molecules of a substance are in fixed positions, the can only vibrate but can not translate. In the liquid state, the molecules acquire a greater degree of freedom and can translate in addition to vibration and rotation. In a gas the molecules are infinitely free and translate at high velocities.
Arrow 1 shows a phase change from liquid to gas. This occurs during boiling. This phase change is possible because the liquid molecules acquire energy in the form of heat supplied during boiling thereby making the molecules of the liquid to speed up their motion and escape the liquid surface as vapour.
The answer is b) 12 i believe
