Answer:
The process of dissolving is exothermic when more energy is released when water molecules “bond” to the solute than is used to pull the solute apart. Because more energy is released than is used, the molecules of the solution move faster, making the temperature increase.
Project the image Endothermic Dissolving.
The process of dissolving is endothermic when less energy is released when water molecules “bond” to the solute than is used to pull the solute apart. Because less energy is released than is used, the molecules of the solution move more slowly, making the temperature decrease.
Answer: Compounds.
Explanation:
Compounds are formed when an unstable element combines with other elements, they do this by sharing electrons within their outmost shell. Compounds forms when there is a chemical bonding between two or more elements. Examples of compounds includes carbon dioxide (C, O) water (H and O), Sodium chloride (Na, Cl), methane, etc.
Answer:
The cat
Explanation:
1) You need to find how many meters per second each thing is sprinting, so you can divide the meters by seconds for each.

2) Per second, the sprinter is able to achieve 8 meters, while the cat can do around 10.5 meters. 10.5 is greater than 8, making the cat faster than the sprinter.
Answer:
26.7% is the percent composition by mass of sulfur in a compound named magnesium sulfate.
Explanation:
Molar mass of compound = 120 g/mol
Number of sulfur atom = 1
Atomic mass of sulfur = 32 g/mol
Percentage of element in compound :

Sulfur :

26.7% is the percent composition by mass of sulfur in a compound named magnesium sulfate.
<span> Au</span>₂(SeO₄)₃
O = -2 × 4 = -8
Se = + 6
So,
(+6 - 8) = -2
Means (SeO₄) contains -2 charge, Now multiply -2 by 3
-2 ₓ 3 = -6
Means,
Au₂ + (-6) = 0
Au₂ = +6
Or,
Au = 6 / 2
Au = +3
Result:
Au = +3
Se = +6
O = -2
Ni(CN)₂
Cyanide (CN⁻) contains -1 charge,
So,
N = -3
C = +2
Then,
Ni + (-1)₂ = 0
Ni - 2 = 0
Or,
Ni = +2
Result:
N = -3
C = +2
Ni = +2