Answer:
Atoms He (Avogadro’s number) → Moles of He (molar mass of He) → Mass of He
• molar mass of He (from the periodic table) = 4.003 g/mol
• Avogadro’s Number: Avogadro’s number gives us the number of entities present in 1 mole: 6.022 × 1023 He atoms in 1 mole of He
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Answer: The speed is equivalent to <u>159.39 kilometers per hour </u>or <u>2.65 kilometers per minute.</u>
Explanation:
Given, The speed of a race car = 99 miles/ hour
To convert the speed into kilometers per hour and kilometers per minute
Since 1 mile = 1.61 kilometers
So, Speed of car = (99 ) x (1.61 )
= 159.39 kilometers per hour.
Also, 1 hour = 60 minutes
Then, Speed of car = (159.39) ÷60
= 2.6565≈2.65 kilometer per minute.
Hence, the speed is equivalent to <u>159.39 kilometers per hour </u>or <u>2.65 kilometers per minute.</u>
Answer:
Sodium sulfide is the chemical compound with the formula Na 2 S, or more commonly its hydrate Na 2 S·9H 2 O. Both are colorless water-soluble salts that give strongly alkaline solutions. When exposed to moist air, Na 2 S and its hydrates emit hydrogen sulfide , which smells like rotten eggs.
I'm not sure if it's right but it's a guess because of the 2Na.
Answer:
E = 17 kJ
Explanation:
The enthalpy of the reaction is:
<u>Where</u>:
Ep: is the energy of the products
Er: is the energy of the reactants
Similarly, the enthalpy of the reaction is related to the activation energy forward (
) and to the activation energy reverse (
) as follows:
Having that ΔH = 44 kJ and = 61 kJ, the activation energy of the reverse reaction is:
Therefore, the activation energy of the reverse reaction is 17 kJ.
I hope it helps you!
Answer:
sorry i never learned this
Explanation:
