Answer : The new pressure of the gas will be, 468.66 atm
Explanation :
Boyle's Law : This law states that pressure of the gas is inversely proportional to the volume of the gas at constant temperature and number of moles.
(At constant temperature and number of moles)
or,

where,
= initial pressure of the gas = 74 atm
= final pressure of the gas = ?
= initial volume of the gas = 190 ml
= final volume of the gas = 30 ml
Now we put all the given values in the above formula, we get the final or new pressure of the gas.


Therefore, the new pressure of the gas will be, 468.66 atm
Answer:
B) conducts electricity
Explanation:
This answer can be answered by the process of elimination. Metals are excellent conductors of electricity, which means A is out, and metals are also known to have medium reactivity and have high melting points, meaning C and D are also out.
It involved knots in strings called quipu. The quipu was not a calculator, rather it was a storage device. Remember that the Incas had no written records and so the quipu played a major role in the administration of the Inca empire since it allowed numerical information to be kept.
Yes. Percent yield shows how efficient one's method is. If his isolated caffeine proved to be at only 1.5%, compared to least 50% as in many of the previous experiments, the student should be very concerned as it shows that something caused the yield to sharply drop.
Answer: -
15.55 M
35.325 molal
Explanation: -
Let the volume of the solution be 1000 mL.
Density of nitric acid = 1.42 g/ mL
Total Mass of nitric acid Solution = Volume of nitric acid x Density of nitric acid
= 1000 mL x 1.42 g/ mL
= 1420 g.
Percentage of HNO₃ = 69%
Amount of HNO₃ = 
= 979.8 g
Molar mass of HNO₃ = 1 x 1 + 14 x 1 + 16 x 3 = 63 g /mol
Number of moles of HNO₃ = 
= 15.55 mol
Molarity is defined as number of moles per 1000 mL
We had taken 1000 mL as volume and found it to contain 15.55 moles.
Molarity of HNO₃ = 15.55 M
Mass of water = Total mass of nitric acid solution - mass of nitric acid
= 1420 - 979.8
= 440.2 g
So we see that 440.2 g of water contains 15.55 moles of HNO₃
Molality is defined as number of moles of HNO₃ present per 1000 g of water.
Molality of HNO₃ = 
= 35.325 molal