Answer:
The temperature remains
Explanation:
The temperature of a boiling substance remains the same because the extra energy is used in phase transition, that is to break the bonds between the molecules that hold them close together in the liquid state. With increased energy the molecules gain enough kinetic energy to overcome inter-molecular forces and change state from liquid to gas
Density = mass /volume of the body. mass = 10.88 g, volume of the liquid displaced= 49.4-43.5=5.9 ml.
density = 10.88/5.9=1.844 g/ml~1.84 g/ml
The volume displaced is exactly the same as that of the body (The Eureka fro Archimedes!)
Answer:
2.94 x 10⁻¹⁴L
Explanation:
To solve this problem, we have to assume that the condition of this water is at standard temperature and pressure, STP.
At STP;
1 mole of gas have a volume of 22.4L
So, let us find the number of moles of this water first;
6.02 x 10²³ molecules can be found in 1 mole of a substance
7.89 x 10⁸ molecules will contain 
= 1.31 x 10⁻¹⁵mole of water
So;
Volume of water = 22.4 x 1.31 x 10⁻¹⁵ = 2.94 x 10⁻¹⁴L
This is a classical C1V1 = C2V2 question. We are given the initial concentration (2.0M), the final concentration (0.5M) and the final volume (200mL). We are asked how many mL of 2.0 M NaBr we require to make up the final concentration and volume, so we are calculating the initial volume (V1)
Therefore:
C1V1 = C2V2
2.0M(V1) = (0.5M)(200.0 mL)
V1 = 50 mL
So 50 mL of NaBr is needed to make a dilution to 0.5M in 200 mL.
