Answer:
Stopwatches versus clocks. To improve reliability repeat the experiment multiple times according to an identical procedure. Record these steps so the experiment can be repeated at any time
Explanation:
Answer: seas
Explanation:
The ancient astronomers thought the mares on the moon were seas.
Answer:
19.8 kg of C₂H₂ is needed
Explanation:
We solve this by a rule of three:
If 1251 kJ of heat are relased in the combustion of 1 mol of acetylene
95.5×10⁴ kJ of heat may be released by the combustion of
(95.5×10⁴ kJ . 1) /1251kJ = 763.4 moles of C₂H₂
Let's convert the moles to mass → 763.4 mol . 26 g/1 mol = 19848 g
If we convert the mass from g to kg → 19848 g . 1kg / 1000g = 19.8 kg
The balanced reaction is
Na2O + H2O --> 2NaOH
If 2.24 moles of sodium oxide react, that means 4.48 moles of NaOH is formed as it is a 1 to 2 stoichiometric relationship.
Now we multiply by the molar mass to get grams.
4.48 moles NaOH * (39.997 grams/1 mole) = 179.2 grams
Your answer is 179. grams.
Glycerol attractive forces are great than water. The harder to break, the more energy is needed.