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3 years ago

Enter a balanced chemical equation for the reaction between potassium metal and liquid water.

Chemistry

1 answer:

Oksanka [162]3 years ago

6 0

Answer:

2K (s) + 2H₂O (l) → 2KOH (aq) + H₂(g)↑

Explanation:

1) Word equation (given)

Potassium + water → ?

2) Kind of reaction

Potassium is an alkali metal.

This is a single replacement reaction.

Alkali metals is the group of metals in the group 1 of the periodic table. These are the most active metals, meaning that they react violently with water releasing hydrogen gas.

Alkali metals can lose an electron to form compounds with oxidation number +1.

The general equation for the reaction of an alkali metal and water is:

Metal + Water → hydroxide + gaseous hydrogen

X + H₂O → XOH(aq) + H₂ (g) ↑

3) Chemical equation

K (s) + H₂O (l) → KOH(aq) + H₂(g)↑

4) Balance

2K (s) + 2H₂O (l) → 2KOH(aq) + H₂(g)↑

There is the same number of each atom on both sides: 2 K in the left and in the right, 4 H in the left and in the right, and 2 oxygen in the left and in the right. So, the equation is balanced.

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Answer:

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3 years ago

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choli [55]

Answer:

When salt is dissolved in water, many physical properties change, among them the so called colligative properties:

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Explanation:

Colligative properties are the physical properties of the solvents whose change is determined by the number of particles (moles or ions) of the solute added.

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The boiling point is the temperature at which the vapor pressure of the liquid equals the atmospheric pressure. Since we have seen that the vapor pressure of water decreases when a solute occupies part of the surface, now more temperature will be required for the water molecules reach the atmospheric pressure. So, the boiling point increases when salt is dissolved in water.

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