Hope it helps for you : )
Answer:
B. exothermic; leaving
Explanation:
The exothermic process releases heat, which causes the surrounding area to increase in temperature.
Your hand is releasing heat and makes the temperature of the ice cube increase, to where it melts.
Answer:
Explanation:
We will need a balanced chemical equation with masses, moles, and molar masses.
1. Gather all the information in one place:
Mᵣ: 18.02
2Na + H₂O ⟶ 2NaOH + H₂
m/g: 72.0
2. Moles of H₂O
3. Moles of Na
The molar ratio is 2 mol Na/1 mol H₂O.
Families are another names for the columns
<span>number of moles are the amount of substance of an element .
number of moles can be calculated as follows;
number of moles = mass present / molar mass of element
molar mass of Ar - 40 g/mol
number of moles of Ar = 22 g / 40 g/mol = 0.55 mol .
there are 0.55 mol of Ar</span>
