Answer:
1. solid, 2.liquid, 3.gas.
When cooled by liquid nitrogen, the balloon shrinks (not as much as the air-filled balloon) and it sinks down on the table. When heating up, the balloon slowly rises and flies up in the air again. Explanation 1: The volume of the balloon decreases by the low temperature, because the gas inside is cooled down.
I don't know what the problem is, but here are some rues to help you out:
- All non-zero figures are significant
- When a zero falls between non-zero digits, that zero is significant.
- When a zero falls after a decimal point, that zero is significant.
- When multiplying and dividing significant figures, the answer is limited to the number of sig figs equal to the least number of sig figs in the problem.
- When adding and subtracting, the answer is limited to the number of decimal places in the number with the least number of decimal places.
I think you means the KO2 reacts with H2O. The equation of this reaction is 4KO2+2H2O->4KOH +3O2. The ratio of mole number of O2 and KO2 is 3:4. So the mole number of O2 produced is 0.500/4*3=0.375 mol.
Answer:
Explanation:
A substance that produces an excess of hydroxide ion (-OH) in aqueous solution.
This is an arrhenius Base
According to the arrhenius theory, a base is a substance that combines with water to produce excess hydroxide ions, OH⁻ in an aqeous solution. Examples are :
- Sodium hydroxide NaOH
- Potassium hydroxide KOH
A substance that produces an excess of hydrogen ion (H+) in aqueous solution
This is an arrhenius Acid
An arrhenius acid is a substance that reacts with water to produce excess hydrogen ions in aqueous solutions.
Examples are;
- Hydrochloric acid HCl
- Hydroiodic acid HI
- Hydrobromic acid HBr