Answer:
0.79 g
Explanation:
Let's introduce a strategy needed to solve any similar problem like this:
- Apply the mass conservation law (assuming that this reaction goes 100 % to completion): the total mass of the reactants should be equal to the total mass of the products.
Based on the mass conservation law, we need to identify the reactants first. Our only reactant is sodium bicarbonate, so the total mass of the reactants is:
We have two products formed, sodium carbonate and carbonic acid. This implies that the total mass of the products is:
Apply the law of mass conservation:
Substitute the given variables:
Rearrange for the mass of carbonic acid:
Answer:
128.4 m
Explanation:
3.604m + 104.29m + 3.1m + 17.41m
Add all the values
= 128.404 m
The significant figure rule for addition is for the sum to have the same number of decimal places as the value with the least number of decimal places. In the addition sentence 3.604m + 104.29m + 3.1m + 17.41m, the value with the least number of decimal places is 3.1, which has 1 decimal place. Therefore, we round our sum so that it also has 1 decimal place.
128.404 m
= 128.4 m
I hope this helps!
Answer:
Group 2
Explanation:
Because group 2 is very reactive and forms salts with other non metals. Example Calcium Chloride. Calcium is from group 2, forms ionic salts with other non metal, and exists as solid at standard temp and pressure.
Answer:
There were 0.00735 moles Pb^2+ in the solution
Explanation:
Step 1: Data given
Volume of the KI solution = 73.5 mL = 0.0735 L
Molarity of the KI solution = 0.200 M
Step 2: The balanced equation
2KI + Pb2+ → PbI2 + 2K+
Step 3: Calculate moles KI
moles = Molarity * volume
moles KI = 0.200M * 0.0735L = 0.0147 moles KI
Ste p 4: Calculate moles Pb^2+
For 2 moles KI we need 1 mol Pb^2+ to produce 1 mol PbI2 and 2 moles K+
For 0.0147 moles KI we need 0.0147 / 2 = 0.00735 moles Pb^2+
There were 0.00735 moles Pb^2+ in the solution