All categories

3 years ago

Which correctly describes the reaction between potassium and excess water?

1 answer:

7 0

Balanced chemical reaction: 2K(s) + 2H₂O(l) → 2KOH(aq) + H₂(g).

KOH is inorganic compound potassium hydroxide, a strong base.
H₂ is hydrogen gas.
In balanced chemical reaction number of atoms on both side of chemical reaction must be same. There are two potassium atoms, four hydrogen atoms and two oxygen atoms on both side of reaction.

You might be interested in

During which season is the sun highest in the sky?

Softa [21]

Answer:

sunmmerrrr

Explanation:

4 0

3 years ago

Read 2 more answers

Help me please i don’t understand the problem

brilliants [131]

Answer:

Atoms are neither created or destroyed.

Explanation:

The end result of a chemical change does not create or destroy any atoms. Matter cannot be created or destroyed, meaning the same amount of atoms exist before and after the change.

5 0

4 years ago

Read 2 more answers

A certain liquid X has a normal freezing point of 7.60 °C and a freezing point depression constant K= 6.90 °C-kg-mol. Calculate

Dmitry [639]

Answer: The freezing point of solution is -5.11°C

Explanation:

Vant hoff factor for ionic solute is the number of ions that are present in a solution. The equation for the ionization of sodium chloride follows:

$NaCl(aq.)\rightarrow Na^{+}(aq.)+Cl^-(aq.)$

The total number of ions present in the solution are 2.

To calculate the molality of solution, we use the equation:

$Molality=\frac{m_{solute}\times 1000}{M_{solute}\times W_{solvent}\text{ in grams}}$

Where,

$m_{solute}$ = Given mass of solute (NaCl) = 7.57 g

$M_{solute}$ = Molar mass of solute (NaCl) = 58.44 g/mol

$W_{solvent}$ = Mass of solvent (liquid X) = 350.0 g

Putting values in above equation, we get:

$\text{Molality of }NaCl=\frac{7.57\times 1000}{58.44\times 350.0}\\\\\text{Molality of }NaCl=0.370m$

To calculate the depression in freezing point, we use the equation:

$\Delta T=iK_fm$

where,

i = Vant hoff factor = 2

$K_f$ = molal freezing point depression constant = 6.90°C/m

m = molality of solution = 0.370 m

Putting values in above equation, we get:

$\Delta T=2\times 6.90^oC/m.g\times 0.370m\\\\\Delta T=5.11^oC$

Depression in freezing point is defined as the difference in the freezing point of water and freezing point of solution.

$\Delta T=\text{freezing point of water}-\text{freezing point of solution}$

$\Delta T$ = 5.11 °C

Freezing point of water = 0°C

Freezing point of solution = ?

Putting values in above equation, we get:

$5.106^oC=0^oC-\text{Freezing point of solution}\\\\\text{Freezing point of solution}=-5.11^oC$

Hence, the freezing point of solution is -5.11°C

7 0

4 years ago

..........................

labwork [276]

Mixtures can be physically separated but compounds must be chemically separated.

PLS MARK ME AS THE BRAINLIEST

4 0

4 years ago

PLEASE HELP ASAP

Kisachek [45]

Answer:

opg

Explanation:

A series of chemical reactions transform Volatile Organic Compounds (VOCs) into substances that combine with nitrogen dioxide to produce PAN (Peroxyacytyl nitrate), yet another element in smog. Nitrogen dioxide in the air also reacts with water vapor to form nitric acid, one of the types of acid in acid rain.

6 0

3 years ago