Answer:
79.8g/dm³
Explanation:
As you can see, the solution in the problem contains 0.5 moles of copper sulfate per dm³. To solve this question we must convert these moles to grams using its molar mass (Molar mass CuSO4 = 159.609g/mol) as follows:
0.5mol CuSO4/dm³ * (159.609g/mol) =
<h3>79.8g/dm³</h3>
<u>Answer:</u> The correct answer is Option 3.
<u>Explanation:</u>
All the radioisotope decay processes follow first order kinetics.
Rate law expression for first order kinetics is given by the equation:

where,
k = rate constant = ?
t = time taken for decay process = 8.32 seconds
a = initial amount of the reactant = 80 mg
a - x = amount left after decay process = 20 mg
Putting values in above equation, we get:

The equation used to calculate half life for first order kinetics:

where,
= half life of the reaction = ?
k = 
Putting values in above equation, we get:

Hence, the correct answer is Option 3.
The question is incomplete, complete question is ;
A deep-sea diver uses a gas cylinder with a volume of 10.0 L and a content of 51.8 g of
and 33.1 g of He. Calculate the partial pressure of each gas and the total pressure if the temperature of the gas is 21°C.Express the pressures in atmospheres to three significant digits separated by commas.
Answer:
Partial pressure of the oxygen gas is 3.91 atm.
Partial pressure of the helium gas is 20.0 atm
Total pressure of the gases is 24.0 atm
Explanation:
Moles of oxygen gas = 
Moles of helium gas = 
Total moles of gas = 
Volume of the cylinder = V = 10.0 L
Total pressure in the cylinder = P = ?
Temperature of the gas in cylinder = T = 21°C = 21 + 273 K = 294 K
PV = nRT ( ideal gas equation )


P = 23.88 atm ≈ 23.9
Partial pressure of the individual gas will be determined by the help of Dalton's law:
partial pressure = Total pressure × mole fraction of gas
Partial pressure of the oxygen gas


Partial pressure of the helium gas


They are important because they are the electrons that help the atom to bond with another atom. They are in the outer most shell. ☺️