All categories

3 years ago

How are covalent network solid similar to ionic solids?

1 answer:

7 0

Ionic solids have high melting points and are rather hard. ... Covalent solids comprise two- or three-dimensional networks of atoms held together by covalent bonds; they tend to be very hard and have high melting points

You might be interested in

Sea level changes occur at a rate of 10 m per 1,000 years. Regional erosion occurs at a rate of 2 m per 1,000 years. Uplift occu

PtichkaEL [24]

<h3>Answer:</h3>

The rate of sea level change is the fastest

<h3>Explanation:</h3>

To determine the process which is the fastest we need to determine the rate at which each occurs in meters per year.

Rate of sea level changes is 10 m per 1,000 years

Therefore, the rate of sea level change = 10 m ÷ 1000 years

= 0.01 m/yr

Regional erosion occurs at 2 m per 1,000 years

Therefore, Rate in meters per seconds = 2 m ÷ 1,000 years

= 0.002 m/year

Uplift occurs at a rate of 0.1 m per 1,000 years

Thus, rate in meters per seconds = 0.1 m ÷ 1,000 years

= 0.0001 m/yr

Therefore, the rate of sea level change is the fastest at a rate of 0.01 meter/year

4 0

4 years ago

1. Write the equilibrium expressions for the following reactions:

Paha777 [63]

I really don’t know sorry uhm I will answer when I know it probably like 30 mins

7 0

3 years ago

Rank these acids according to their expected pKa values.

givi [52]

Answer:

According to their expected pKa values, the order of those acids should be:

1- Cl2CHCOOH is the strongest acid and the lowest pKa.

2- ClCH2COOH is a strong acid, but no more than the first. Medium pKa value.

3- ClCH2CH2COOH is a strong acid, but no more than the two previous acids. High pKa value.

4- CH3CH2COOH is the weakest acid, so the highest pKa value.

Explanation:

The pKa values are the negative logarithm of dissociation constant. It represents the relative strengths of the acids. Stronger acids show smaller pKa values and weak acids present larger pKa value. The stronger the acid, the weaker it's the conjugate base. The larger the pKa of the conjugate base, the stronger the acid. The strength of an acid is inversely related to the strength of its conjugate.

Conjugate bases are the substance that has one less proton than the parent acid. The conjugate base of the acid presented in the problem are:

ClCH2COOH -> ClCH2COO- + H+

ClCH2CH2COOH -> ClCH2CH2COO- + H+

CH3CH2COOH -> CH3CH2COO- + H+

Cl2CHCOOH -> Cl2CHCOO - + H+

Cl2CHCOOH. The negative charge presented on its conjugate base is by resonance and inductive effect. This is the strongest acid.

ClCH2COOH. A negative charge is stabilized by resonance and electron-withdrawing but only one atom is present. So this acid is less strong than the first one.

ClCH2CH2COOH. The negative charge is stabilized by resonance and electron-withdrawing atom but the effect is less compared to the two acids showed previously.

CH3CH2COOH. The negative charge is stabilized by resonance and destabilized due to CH3 group. This is the weakest acid among the problem.

Stronger acids have smaller pKa values and weak acids have larger pKa values. Due to the information present in this problem, Cl2CHCOOH is the strongest acid and the lowest pKa. CH3CH2COOH is the weakest acid, so the highest pKa value.

Finally, we can conclude that according to their expected pKa values, the order of those acids should be:

1- Cl2CHCOOH is the strongest acid and the lowest pKa.

2- ClCH2COOH is a strong acid, but no more than the first. Medium pKa value.

3- ClCH2CH2COOH is a strong acid, but no more than the two previous acids. High pKa value.

4- CH3CH2COOH is the weakest acid, so the highest pKa value.

3 0

3 years ago

Which of the following concerning solutions is/are correct? 1. The solvent in a mixture of gases is generally considered to be t

pshichka [43]

Answer: 1. The solvent in a mixture of gases is generally considered to be the substance in greater amount. 2. The solid dissolved in a solution is known as the solute. 3. Solid solutions are called alloys.

Explanation:

A binary solution is made up of two components ,called as solute and another as solvent.

A solute is defined as the component which is present in smaller proportion. It can be in solid, liquid or gaseous phase. A solvent is defined as the component which is present in larger proportion in a solution. It can be in solid, liquid or gaseous phase.

Usually in liquid solutions , solid acts as solute and liquid acts as solvent. For example: In salt solution, salt is the solute and water is the solvent.

Solid solutions contains solid as solute and solid as solvent. These are called as alloys. For example : In brass, zinc is the solute and copper is the solvent.

4 0

3 years ago

Which of the following choices are types of energy? (Select all that apply) A.kinetic energy B.physical energy C.thermal energy

Aleksandr-060686 [28]

Answer:

kinetic, thermal and chemical not physical

7 0

4 years ago