Answer:iron and oxygen combining to make rust. vinegar and baking soda combining to make sodium acetate, carbon dioxide and water
Explanation:
Answer:
The correct answer is Mn goes from +7 to +2.
Explanation:
The permanganate ion (Mn04-) forming by Oxygen (-2 its oxidation state) and the Mn (+7), throwing the count: +7 + (-2 x4) = -1 (the charge of the ion). Said permanganate ion is reduced in the reaction to Mn2 +.
The chemical formula for calcium hydroxide is Ca(OH)₂ and that of nitric acid is HNO₃. By these chemical formula it can be deduced that the number of equivalents per mole of Ca(OH)₂ is 2 because of 2 OH⁻ and for HNO₃ is 1 because of H⁺.
For the neutralization reaction, the number of equivalents should be equal.
V₁n₁ = V₂n₂
Substituting the known values and with the incorporation of the concept above,
(V₁)(0.0250 mol/L)(2 equivalents/mol) = (33.50 mL)(0.020 mol/L)(1 equivalent/mol)
V₁ = 13.4 mL
Hence, the volume of calcium hydroxide needed is approximately equal to 13.4 mL.
Answer:
B. It increases.
Explanation:
- We can use the general law of ideal gas: <em>PV = nRT.</em>
where, P is the pressure of the gas in atm.
V is the volume of the gas in L.
n is the no. of moles of the gas in mol.
R is the general gas constant,
T is the temperature of the gas in K.
It is clear that, at constant P, the volume of the gas (V) is directly proportional to the temperature of the gas.
<em>V ∝ T.</em>
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<em>So, If a balloon is heated, the volume of the air in the balloon if the pressure is constant:</em>
B. It increases.
Answer:
58g
Explanation:
In order to solve this problem, you must take a look at the solubility graph for potassium nitrate.
Now, the solubility graph shows you how much solute can be dissolved per 100g of water in order to make an unsaturated, a saturated, or a supersaturated solution.
You're looking to make a saturated potassium nitrate solution using
50g of water at 60∘C. Your starting point will be to determine how much potassium nitrate can be dissolved in 100g of water at that temperature in order to have a saturated solution.
As you can see, the curve itself represents saturation.
If you draw a vertical line that corresponds to 60∘C and extend it until it intersects the curve, then draw a horizontal line that connects to the vertical axis, you will find that potassium has a solubility of about
115g per 100g of water. Your answer is 58g of potassium nitrate