All categories

3 years ago

What role do valence electrons play in the formation of compounds from elements?

1 answer:

n200080 [17]3 years ago

6 0

Valence electrons predict how many bonds will happen: a single bond, double bond, or triple bond. Also, the valence electrons tell us what type of bond will happen: ionic, covalent, or metallic.

You might be interested in

What is the pH of a KOH solution that has [H ] = 1. 87 × 10–13 M? What is the pOH of a KOH solution that has [OH− ] = 5. 81 × 10

vlada-n [284]

pH is the hydrogen ion concentration and pOH is the hydroxide ion concentration in the solution. pH KOH is 12.73, pOH KOH is 2.24 and pH NaCl is 7.

pH is the negative log of the hydrogen ion concentration and pOH is the negative log of the hydroxide ion concentration.

The relation between the pH and pOH can be given as, $\rm pOH = 14 - pH$

The pH of KOH can be calculated by the formula,

$\rm pH = \rm -log [H^{+}]$

In the first case, the concentration of the KOH is $1. 87 \times 10^{-13}\;\rm M$

Substituting values in the equation:

$\begin{aligned} \rm pH &= \rm -log [H^{+}]\\\\&= \rm -log [1. 87 \times 10^{-13}\;\rm M ]\\\\&= 12.73\end{aligned}$

Hence, the pH of KOH is 12.73.

<u />

pOH of KOH can be calculated by the formula,

$\rm pOH = \rm -log [OH^{-}]$

The hydroxide concentration of the KOH solution is $5. 81 \times 10^{-3}\;\rm M$

Substituting value in the equation:

$\begin{aligned} \rm pOH &= \rm -log [OH^{-}]\\\\&= \rm -log [5. 81 \times 10^{-3}\;\rm M ]\\\\&= 2.24 \end{aligned}$

Hence, the pOH of KOH is 2.24

<u />

The pH of NaCl can be calculated by the formula,

$\rm pH = \rm -log [H^{+}]$

In the third case, the concentration of the NaCl is $1. 00\times 10^{-7}\;\rm M$

Substituting values in the equation:

$\begin{aligned} \rm pH &= \rm -log [H^{+}]\\\\&= \rm -log [1. 00 \times 10^{-7}\;\rm M ]\\\\&= 7 \end{aligned}$

Hence, the pH of KOH is 7.0.

Therefore, KOH is basic and NaCl is approximately neutral.

Learn more about pH and pOH here:

brainly.com/question/13885794

3 0

3 years ago

Calculate the molality of 75.0 grams of MgCl2 (molar mass=95.21 g/mol) dissolved in 500.0 g of solvent.

nordsb [41]

<u>Answer:</u> The molality of magnesium chloride is 1.58 m

<u>Explanation:</u>

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

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

Where,

$m_{solute}$ = Given mass of solute (magnesium chloride) = 75.0

$M_{solute}$ = Molar mass of solute (magnesium chloride) = 95.21 g/mol

$W_{solvent}$ = Mass of solvent = 500.0 g

Putting values in above equation, we get:

$\text{Molality of }MgCl_2=\frac{75.0\times 1000}{95.21\times 500.0}\\\\\text{Molality of }MgCl_2=1.58m$

Hence, the molality of magnesium chloride is 1.58 m

5 0

4 years ago

Read 2 more answers

Can you please solve this question???

Mandarinka [93]

Answer:

1 is Argon

2 is Kalium

3 is Calcium

ii)

Y belongs to alkaline metals

Z belongs to alkaline earth metals

iii)

Kalium (Y) is alkaline metal

8 0

3 years ago

NaCl(aq) AgNO3(aq) → AgCl(s) NaNO3(aq) : NaCl(aq) AgNO3(aq) \rightarrow AgCl(s) NaNO3(aq) : blank H2SO4(aq) 2 LiOH(aq) → 2 H2O(l

Elena L [17]

The question is incomplete, here is a complete question.

Categorize each reaction into types of chemical reactions.

(1) $NaCl(aq)+AgNO_3(aq)\rightarrow AgCl(s)+NaNO_3(aq)$

(2) $H_2SO_4(aq)+2LiOH(aq)\rightarrow 2H_2O(l)+Li_2SO_4(aq)$

(3) $HCl(aq)+(NH_4)_2S(aq)\rightarrow H_2S(g)+2NH_4Cl(aq)$

(4) $Mg(s)+Cu(NO_3)_2(aq)\rightarrow Mg(NO_3)_2(aq)+Cu(s)$

Answer :

(1) Precipitation reaction

(2) Neutralization reaction

(3) Double-displacement reaction

(4) Single replacement reaction

Explanation :

(1) The balanced chemical reaction is:

$NaCl(aq)+AgNO_3(aq)\rightarrow AgCl(s)+NaNO_3(aq)$

This reaction is a precipitation reaction in which an insoluble salt formed when two aqueous solutions are combined. The insoluble salt that settle down in the solution is known an precipitate.

(2) The balanced chemical reaction is:

$H_2SO_4(aq)+2LiOH(aq)\rightarrow 2H_2O(l)+Li_2SO_4(aq)$

This is a neutralization reaction in which an acid react with a base react to give salt and water as a product that means it reacts to give a neutral solution.

(3) The balanced chemical reaction is:

$HCl(aq)+(NH_4)_2S(aq)\rightarrow H_2S(g)+2NH_4Cl(aq)$

The given reaction is a double-displacement reaction in which the cation of two reactants molecule exchange their places to give two different products.

(4) The balanced chemical reaction is:

$Mg(s)+Cu(NO_3)_2(aq)\rightarrow Mg(NO_3)_2(aq)+Cu(s)$

This reaction is a single replacement reaction in which the the more reactive element replace the less reactive element.

8 0

3 years ago

Give an example of a system that has energy.

Savatey [412]

Do you think black schools had budgets to purchase update textbooks

7 0

3 years ago