Answer:
Explanation:
a ) Total mixture = 4.656 g
Sand recovered = 2.775 g
percent composition of sand in the mixture
= (2.775 g / 4.656 g ) x 100
= 59.6 % .
b )
Total of sand and salt recovered = 2.775 g + .852 g = 3.627 g .
Total mixture = 4.656 g
percent recovery = (3.627 / 4.656 ) x 100
= 77.9 % .
Reduction half reaction: Cu²⁺(aq) + 2e⁻ → Cu⁰(s).
Oxidation half reaction: NO₂⁻(aq) + H₂O(l) → NO₃⁻(aq) + 2H⁺(aq) + 2e⁻.
Balanced chemical reaction:
Cu²⁺(aq) + NO₂⁻(aq) + H₂O(l) → Cu(s) + NO₃⁻(aq) + 2H⁺(aq).
Copper is reduced from oxidation number +2 (Cu²⁺) to oxidation number 0 (Cu) and nitrogen is oxidized from oxidation number +3 (in NO₂⁻) to oxidation number +5 (in NO₃⁻).
Answer:

Explanation:
Since we are given the mass, specific heat, and change in temperature, we should use this formula for heat:

The substance's mass is 450.0 grams, the specific heat is 1.264 J/g°C, and the change in temperature is 7.1 °C.

Substitute the values into the formula.

Multiply the first 2 values together. The grams will cancel out.

Multiply again. This time, the degrees Celsius cancel out.

<u>4038.48 Joules</u> of heat energy are released.
Answer:
If an atom, ion, or molecule is at the lowest possible energy level, it and its electrons are said to be in the ground state. If it is at a higher energy level, it is said to be excited, or any electrons that have higher energy than the ground state are excited
Explanation:
pls mark brainliest
C is wrong, the real answer is B: to add tartness, and the reason why is because citric acid comes from jam, jellies, and more! And that is why the answer B is the correct answer.
Hope this helped!
Nate
(P.S. if you buy jams and real the ingredients, it will say "citric acid." :))