Answer:- 0.800 moles of the gas were collected.
Solution:- Volume, temperature and pressure is given for the gas and asks to calculate the moles of the gas.
It is an ideal gas law based problem. Ideal gas law equation is used to solve this. The equation is:
PV=nRT
Since it asks to calculate the moles that is n, so let's rearrange this for n:
V = 19.4 L
T = 17 + 273 = 290 K
P = 746 mmHg
we need to convert the pressure from mmHg to atm and for this we divide by 760 since, 1 atm = 760 mmHg
P = 0.982 atm
R = 
Let's plug in the values in the equation to get the moles.
n = 0.800 moles
So, 0.800 moles of the gas were collected.
Answer: After three half-lives 1/8 (12.5%) of the original sample remains
I don’t know about 3 but I know that 4 is solid, 5 is you’ll feel the vibration first, 6 is you’ll see the lightning first because the speed of light is faster than the speed of sound and 7 is sound waves need a medium to travel and light waves don’t, sound waves are longitudinal and light waves are transverse, and sound waves are mechanical waves while light waves are electromagnetic waves
Answer:
Depends, but in most cases, 2.
It's best to use as many digits as possible to keep it accurate.
Explanation:
This varies between teachers, as most schools go with 2 decimal places.
This is something that depends in your situation.
You technically want as many decimals as possible to keep it as accurate, but most people stick with 2.
I personally do 3, and commonly do 5 sometimes.
