The number of grams of NaOH that are needed to make 500 ml of 2.5 M NaOH solution
calculate the number of moles =molarity x volume/1000
= 2.5 x 500/1000 = 1.25 moles
mass = moles x molar mass of NaOH
= 1.25 x40= 50 grams of NaOH
Answer:
The volume of hydrogen gas produced at STP is 4.90 liters.
Explanation:

Moles of aluminium =
According to reaction , 2 moles of aluminium gives 3 moles of hydrogen gas.
Then 0.1333 moles of aluminium will give:
of hydrogen gas
Volume of 0.2 moles of hydrogen gas at STP = V
Temperature at STP = T = 298.15 K
Pressure at STP = P = 1 atm
n = 0.2 mol
PV = nRT (Ideal gas equation)

The volume of hydrogen gas produced at STP is 4.90 liters.
The balanced equation for the above reaction is;
2K + Cl₂ ---> 2KCl
Stoichiomtery of K to KCl is 2:2
Potassium is the limiting reactant which is fully consumed in the reaction. The amount of product formed depends on amount of limits reactant present.
Number of moles of K reacted - 6.75 g/ 39 g/mol = 0.17 mol
Therefore number of KCl moles formed - 0.17 mol
Mass of KCl formed - 0.17 mol x 74.5 g/mol = 12.67 g
To answer this item, we solve first for the mass of the solution by multiplying the density by the volume. That is,
m = (density)(volume)
Substituting the known values,
m = (1.50 g/mL)(5L)(1000 mL/1L)
m = 7500 grams
To determine the mass of the salt in the solution, multiply the calculated mass of the solution by the decimal equivalent of the percent salt in the solution.
m of salt = (7500 g)(0.33)
m of salt = 2475 grams
<em>Answer: 2475 grams</em>
Answer:
1
Explanation:
There is only one calcium atom because the subscript 3 applies only to the oxygen. Outside of the parentheses, the subscript 2 only applies to the chlorate ion. Therefore, there is only one calcium atom because there are no coefficients and subscripts. (Also drawing it out will help)