Ph is a scale that ____ the audacity or basicity of a solution along the range of zero to 14

In an aqueous solution, 42% of a substance dissociates to release hydronium ions. Which of the following statements is true for

const2013 [10]

Answer: The statement it is a weak acid is true for the substance.

Explanation:

An acid that dissociates completely when dissolved in water to give hydrogen $(H^{+})$ or hydronium $(H_{3}O^{+})$ ions is called a strong acid.

For example, HCl is a strong acid.

$HCl + H_{2}O \rightarrow H_{3}O^{+} + Cl^{-}$

An acid that dissociates partially or weakly when dissolved in water to given hydrogen or hydronium ions is called a weak acid.

For example, $CH_{3}COOH$ is a weak acid.

$CH_{3}COOH \rightleftharpoons CH_{3}COO^{-} + H_{3}O^{+}$

A strong base is a base which when dissolved in water then it dissociates completely to give hydroxide ions.

For example, NaOH is a strong acid.

A weak base is a base which when dissolved in water then it dissociates partially or weakly to give hydroxide ions.

For example, $NH_{3}$ is a weak base.

Hence, in an aqueous solution where 42% of a substance dissociates to release hydronium ions shows that the dissociation is less than 50%. This means that substance is dissociating weakly so, it is a weak acid.

Thus, we can conclude that the statement it is a weak acid is true for the substance.

5 0

3 years ago

g All of the molecules below have polar bonds but only one of the molecules is a polar molecule. Which one is a polar molecule?

lbvjy [14]

Answer: $NF_3$

Explanation:

Geometrical symmetry of the molecule and the polarity of the bonds determine the polarity of the molecule.

The molecule that has zero dipole moment that means it is a geometrically symmetric molecule and the molecule which has some net dipole moment means it is a geometrically asymmetric molecule.

As the molecule is symmetric, the dipole moment will be zero as dipole moments cancel each other and the molecule will be non-polar.

As the molecule is asymmetric, the dipole moment will not be zero and the molecule will be polar.

Example: $NF_3$

Thus, we can say that $NF_3$ is a polar molecule.

4 0

3 years ago

Assuming that an acetic acid solution is 12% by mass and that the density of the solution is 1.00 g/mL, what volume of 1 M NaOH

Doss [256]

Explanation:

Let us assume that total mass of the solution is 100 g. And, as it is given that acetic acid solution is 12% by mass which means that mass of acetic acid is 12 g and 88 g is the water.

Now, calculate the number of moles of acetic acid as its molar mass is 60 g/mol.

No. of moles = $\frac{mass}{\text{molar mass}}$

= $\frac{12 g}{60 g/mol}$

= 0.2 mol

Molarity of acetic acid is calculated as follows.

Density = $\frac{mass}{volume}$

1 g/ml = $\frac{100 g}{volume}$

volume = 100 ml

Hence, molarity = $\frac{\text{no. of moles}}{volume}$

= $\frac{0.2 mol}{0.1 L}$

= 2 mol/l

As reaction equation for the given reaction is as follows.

$NaOH + CH_{3}COOH \rightarrow CH_{3}COONa + H_{2}O$

So, moles of NaOH = moles of acetic acid

Let us suppose that moles of NaOH are "x".

$x \times 1 M = 10 mL \times 2 M$ (as 1 L = 1000 ml)

x = 20 L

Thus, we can conclude that volume of NaOH required is 20 ml.

6 0

4 years ago

Which statement is true for photosynthesis

grigory [225]

Answer: all of them duuuuuuuuuuuuuuuuuuuuuuuuuuuuu

5 0

3 years ago

When a substance is entering a phase change, the gain or loss of heat is a result of:______.

nydimaria [60]

When a substance is entering a phase change, the gain or loss of heat is a result of energy gained or lost in forming or breaking intermolecular interaction.

The constant temperatures occur when a substance is undergoing a phase transition. If heat is removed from a substance , such as in freezing and condensation , then the process is exothermic . In this instance , heat is decreasing the speed of the molecules causing then move slower.

Example : liquid to solid and gas to liquid .

These changes release heat to the surrounding.

To learn more about phase change,

brainly.com/question/12390797

#SPJ4

4 0

2 years ago