Answer:
option . D
Increase in temperature
is an indicator of a chemical reaction
hope it helps
Exothermic releases energy(heat) from the system to the surrounding
endothermic takes energy (heat) from the surrounding to the system
Answer:
A solution of sugar that contains the maximum amount of sugar that will dissolve is a saturated solution.
Explanation:
A saturated solution is a solution that contains as much solute as can dissolve in a given solvent at a given temperature.
for you the solute is sugar
Answer:
- <em>1.34 × 10²⁴ molecules</em>
Explanation:
To calculate the <em>number of molecules of sodium oxide that will be created if 275 grams of sodium reacts with excess oxygen</em>, use the chemical equation to calculate the number of moles and then multiply by Avogadro's number.
<u>1) Balanced chemical equation (given):</u>
<u>2) Mole ratio:</u>
<u>3) Calculate the number of moles in 275 g of Na:</u>
- n = mass in grams / molar mass
- mass of Na = 275 g
- molar mass of Na₂O = 61.9789 g/mol
- n = 275 g / 61.9789 g/mol = 4.437 mol of Na
<u>4) Set a proportion to find the number of moles of product (Na₂O):</u>
- 2 mol Na₂O / 4 mol Na = x / 4.437 mol Na
- x = 4.437 / 2 mol Na₂O = 2.2185 mol Na₂O
<u>5) Convert the number of moles to number of molecules:</u>
- # molecules = n × 6.022 × 10²³ molecules/mol = 2.2185 mol × 6.022 × 10²³ molecules/mol = 1.34 × 10²⁴ molecules (rounded to 3 significant figures).