Answer:
1. 3.70 g Na₂CO₃·10H₂O
2. 50.0 mL of the first solution
Explanation:
1. Prepare the solution
(a) Calculate the molar mass of Na₂CO₃·10H₂O

The molar mass of Na₂CO₃·10H₂O is 286.15 g/mol.
(b) Calculate the moles of Na₂CO₃·10H₂O

(c) Calculate the mass of Na₂CO₃·10H₂O

2. Dilute the solution
We can use the dilution formula to calculate the volume needed.
V₁c₁ = V₂c₂
Data:
V₁ = ?; c₁ = 0.0500 mol·L⁻¹
V₂ = 100 mL; c₂ = 0.0250 mol·L⁻¹
Calculation:

Please mark me brainiest!
The reason why you don’t see solid or liquid oxygen is because oxygen is a natural occurring gas. Gas can not be solid or liquid because there is too much energy to have volume/shape. That’s why you see oxygen tanks, as the tank keeps the gas contained and that is why you can’t see it in the air outside or in something like H20 (water).
Hope this helps :)
Just don’t open the link in the other answer. It’s a scam...
This is true, think of silver, gold, etc— those are heated to make them liquid
Answer:Reliability
Explanation:
Reliability of a test refers to how consistently a test measures a characteristic under the same conditions.
Reliability can be defined as the degree of consistency of which a chemical test gives a similar result. measure. A test is said to be highly reliable when it gives the same repeated result under the same conditions of measure.
But when a test gives different results under the same condition of measure it has a low reliability.
Hence, If a test yields consistent results every time it is used, it has a high degree of reliability.