12➡6➡3➡1.5
① ② ③
3 half life = 252
half life = 84days
Answer:
See Explanation
Explanation:
Because you have to get through the d-block electron configurations for the rest of the p-block elements which is a hassle to do. You need to know how to account for electron stability, from which subshell to remove electrons, etc. because it is all weird for d-block.
Answer:
Calculate the mass percent of a potassium nitrate solution when 15.0 g KNO3 is dissolved in 250 g
of water.
2. Calculate the mass percent of a sodium nitrate solution when 150.0 g NaNO3 is dissolved in 500 mL
of water. Hint: 1 mL water = 1 g water
3. Calculate the weight of table salt needed to make 670 grams of a 4.00% solution.
4. How many grams of solute are in 2,200 grams of a 7.00% solution?
5. How many grams of sodium chloride are needed to prepare 6,000 grams of a 20% solution?
Mass Percent = Grams of Solute
Grams of Solution X 100%
100%
Grams of Solute = Grams of Solution X Mass Percent
= 26.8 grams NaCl
= 670 grams X 4.00%
100%
100%
Grams of Solute = Grams of Solution X Mass Percent
= 154 grams solute
= 2,200 grams X 7.00%
100%
100%
Grams of Solute = Grams of Solution X Mass Percent
= 1,200 grams NaCl
= 6,000 grams X 20.0%
100%
Explanation:
Answer:
The new pressure exerted by the He, is 1266.6 Torr
Explanation:
A typical problem of gases where the volume is increased and the moles and T° keeps on constant. This is an indirect proportion because when the volume of the flask is increased, pressue decreases because molecules collide to a lesser extent with the walls of the vessel.
P₁ . V₁ = P₂ . V₂
760 Torr . 5L = P₂ . 3L
P₂ = (760 Torr . 5L) / 3L
P₂ = 1266.6 Torr