The density is calculated as mass per volume, so if we want to solve for mass, we would multiply density by volume.
For Part A: if we have a density of 0.69 g/mL, and a volume of 280 mL, multiplying these will give a mass of: (0.69 g/mL)(280 mL) = 193.2 g. Rounded to 2 significant figures, this is 190 g gasoline.
For Part B: if we have a density of 0.79 g/mL, and a volume of 190 mL, multiplying these will give a mass of: (0.79 g/mL)(190 mL) = 150.1 g. Rounded to 2 significant figures, this is equal to 150 g ethanol.
Answer:
C) 0.121 M
Explanation:
HCl + H₂O = H₃O⁺ + OH⁻
.121M .121M
HCl is a strong acid . It will dissociate almost 100 % so the concentration of acid and hydronium ion formed will be equal . It is to be noted that hydronium ion is formed due to association of H⁺ and H₂O . H⁺ is formed due to ionisation of HCl .
So concentrtion of hydronium ion ( H₃O⁺ ) will be .121 M.
Answer: d) -705.55 kJ
Explanation:
Heat of reaction is the change of enthalpy during a chemical reaction with all substances in their standard states.

Reversing the reaction, changes the sign of 


On multiplying the reaction by
, enthalpy gets half:


Thus the enthalpy change for the given reaction is -705.55kJ
Answer:
THE VOLUME OF THE BALLOON IS 1.45 L
Explanation:
At sea level:
Volume = 2 L
Pressure = 1 atm
Temperature = 12 °C
At 30000 ft altitude:
Pressure = 0.30 atm
Temperature = -55°C
Volume = unknown
Using the general gas formula:
P1 V1 / T1 = P2 V2 / T2
Re-arranging the formula by making V2 the subject of the equation, we have;
V2 = P1 V1 T2 / T1 P2
V2 = 1 * 2 * 12 / 0.30 * 55
V2 = 24 / 16.5
V2 = 1.45 L
The volume of the balloon at the temperature of -55 C and 0.30 atm is 1.45 L