Answer: 52.17%
Explanation:
Number of matches in the box = 46
Number of matches that lit on the first strike = 22
Number of matches that did not light on the first strike = 46 - 22 = 24
Therefore, the percentage of the matches in the box did not light on the first strike will be:
= (Number of matches that did not light on the first strike / Number of matches in the box) × 100
= 24/46 × 100
= 52.17%
Therefore, the percentage of the matches in the box that did not light on the first strike is 52.17%.
Answer:
The answer is A. Polar covalent; negatively
Explanation:
Hydrogen bonds form between molecules containing polar covalent bond the hydrogen bond is been a hydrogen atom of one molecule and a partially negative charged atom of another.
Example 
(water):- It contain a slight positive charge on one side and a slight negative charge on the other.
A. The molecules of solids are close together and compact, liquids are spread out but not too far apart, and gas molecules are really far apart.
B. Increase in temperature causes pressure to go up. Decrease in temperature cause pressure to go down
Answer:
Boiling point of the solution is 100.78°C
Explanation:
This is about colligative properties.
First of all, we need to calculate molality from the freezing point depression.
ΔT = Kf . m . i
As the solute is nonelectrolyte, i = 1
0°C - (-2.79°C) = 1.86 °C/m . m . 1
2.79°C / 1.86 m/°C = 1.5 m
Now, we go to the boiling point elevation
ΔT = Kb . m . i
Final T° - 100°C = 0.52 °C/m . 1.5m . 1
Final T° = 0.52 °C/m . 1.5m . 1 + 100°C → 100.78°C
Answer:
B
Explanation:
Heating a piece of iron until it glows.
