B. i took the test and got it right
Answer:
Labor unions were created in order to help the workers with work-related difficulties such as low pay, unsafe or unsanitary working conditions, long hours, and other situations. ... Sometimes the unions organized strikes in order to try to change the conditions of the workers.
Explanation:
Using ideal gas equation,
P\times V=n\times R\times T
Here,
P denotes pressure
V denotes volume
n denotes number of moles of gas
R denotes gas constant
T denotes temperature
The values at STP will be:
P=1 atm
T=273 K
R=0.0821 atm L mol ⁻¹
Mass of HCl given= 49.8 g
Molar mass of HCl given=36.41
Number of moles of gas, n= \frac{Given mass of the substance}{Molar mass of the substance}
Number of moles of gas, n= \frac{49.8}{36.46}
Number of moles of gas, n= 1.36
Putting all the values in the above equation,
V=\frac{1.36\times 0.0821\times 273}{1}
V=30.6 L
So the volume will be 30.6 L.
11. ionic charge +1, helium.
12. ionic charge 2-, neon.
13. ionic charge 3+, neon.
Answer:
333.7g of antifreeze
Explanation:
Freezing point depression in a solvent (In this case, water) occurs by the addition of a solute. The law is:
ΔT = Kf × m × i
Where:
ΔT is change in temperature (0°C - -20°C = 20°C)
Kf is freezing point depression constant (1.86°C / m)
m is molality of solution (moles solute / 0.5 kg solvent -500g water-)
i is Van't Hoff factor (1, assuming antifreeze is ethylene glycol -C₂H₄(OH)₂)
Replacing:
20°C = 1.86°C / m × moles solute / 0.5 kg solvent × 1
5.376 = moles solute
As molar mass of ethylene glycol is 62.07g/mol:
5.376 moles × (62.07g / 1mol) = <em>333.7g of antifreeze</em>.
