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3 years ago

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Which pair of substances would most likely result in the production of a solid when reacting with a base? litmus and phenolphtha

lein soluble metal salt and carbon dioxide acids and water hydrogen ions and soaps

2 answers:

svet-max [94.6K]3 years ago

8 0

<h3><u>Answer;</u></h3>

<em>Soluble metal salt and carbon dioxide</em>

<h3><u>Explanation;</u></h3>

Both <u><em>soluble metal salt and carbon dioxide</em></u> may react with a base to form a solid or what we call a precipitate.

For instance when <u><em>carbon dioxide is bubbled through a solution of calcium hydroxide, it results to the formation or precipitate calcium carbonate.</em></u>

<em>Ca(OH)₂(aq) + CO₂(g) → CaCO₃(s) + H₂O(l)</em>

For the case of a soluble metal salt; an example is calcium nitrate, which is <em><u> a soluble metal salt, when reacted with a base like sodium hydroxide, it results to the formation of a solid calcium hydroxide</u></em> and sodium nitrate, a reaction called precipitation reaction.

<em>Ca(NO₃)₂(aq) + NaOH (aq)→ Ca(OH)₂(s) + NaNO₃(aq)</em>

iren2701 [21]3 years ago

6 0

Answer:

It is B on e2020

Explanation:

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What is poly mineralic rock

Art [367]

A rock with different rocks combined to make it

Like quartzite is made up of quartz but granite is made of quartz , feildspar and mica

Hope this helps

7 0

3 years ago

Read 2 more answers

Your job is to determine the concentration of ammonia in a commercial window cleaner. In the titration of a 25.0 mL sample of th

ruslelena [56]

Answer:

The initial concentration of ammonia is 0.14 M and the pH of the solution at equivalence point is 5.20

<u>Explanation:</u>

To calculate the number of moles for given molarity, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}$ .....(1)

Molarity of HCl solution = 0.164 M

Volume of solution = 23.8 mL = 0.0238 L (Conversion factor: 1 L = 1000 mL)

Putting values in equation 1, we get:

$0.164M=\frac{\text{Moles of HCl}}{0.0238L}\\\\\text{Moles of HCl}=(0.146mol/L\times 0.0238L)=0.0035mol$

The chemical equation for the reaction of ammonia and HCl follows:

$NH_3+HCl\rightarrow NH_4^++Cl^-$

By Stoichiometry of the reaction:

1 mole of HCl reacts with 1 mole of ammonia

So, 0.0035 moles of HCl will react with = $\frac{1}{1}\times 0.0035=0.0035mol$ of ammonia

Calculating the initial concentration of ammonia by using equation 1:

Moles of ammonia = 0.0035 moles

Volume of solution = 25 mL = 0.025 L

Putting values in equation 1, we get:

$\text{Initial concentration of ammonia}=\frac{0.0035mol}{0.025L}=0.14M$

By Stoichiometry of the reaction:

1 mole of ammonia produces 1 mole of ammonium ion

So, 0.0035 moles of ammonia will react with = $\frac{1}{1}\times 0.0035=0.0035mol$ of ammonium ion

Calculating the concentration of ammonium ion by using equation 1:

Moles of ammonium ion = 0.0035 moles

Volume of solution = [23.8 + 25] mL = 48.8 mL = 0.0488 L

Putting values in equation 1, we get:

$\text{Molarity of ammonium ion}=\frac{0.0035mol}{0.0488L}=0.072M$

To calculate the acid dissociation constant for the given base dissociation constant, we use the equation:

$K_w=K_b\times K_a$

where,

$K_w$ = Ionic product of water = $10^{-14}$

$K_a$ = Acid dissociation constant

$K_b$ = Base dissociation constant = $1.8\times 10^{-5}$

$10^{-14}=1.8\times 10^{-5}\times K_a\\\\K_a=\frac{10^{-14}}{1.8\times 10^{-5}}=5.55\times 10^{-10}$

The chemical equation for the dissociation of ammonium ion follows:

$NH_4^+\rightarrow NH_3+H^+$

The expression of $K_a$ for above equation follows:

$K_a=\frac{[NH_3][H^+]}{[NH_4^+]}$

We know that:

$[NH_3]=[H^+]=x$

$[NH_4^+]=0.072M$

Putting values in above expression, we get:

$5.55\times 10^{-10}=\frac{x\times x}{0.072}\\\\x=6.32\times 10^{-6}M$

To calculate the pH concentration, we use the equation:

$pH=-\log[H^+]$

We are given:

$[H^+]=6.32\times 10^{--6}M$

$pH=-\log (6.32\times 10^{-6})\\\\pH=5.20$

Hence, the initial concentration of ammonia is 0.14 M and the pH of the solution at equivalence point is 5.20

5 0

3 years ago

How does an increase in temperature affect a chemical reaction??

blsea [12.9K]

An increase in the temperature will speed up the reaction by increasing the frequency and efficiency of the collisions of molecules.

8 0

3 years ago

How does molecular attraction affect the amount of energy needed to create a phase change. Think about low, medium, and high

Art [367]

Answer:

When considering phase changes, the closer molecules are to one another, the stronger the intermolecular forces. Good! For any given substance, intermolecular forces will be greatest in the solid state and weakest in the gas state.

In the case of melting, added energy is used to break the bonds between the molecules. ... If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance. The example we will use here is ice melting into water.

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3 years ago

What is the temperature of 4.5 moles of a gas that occupies 50. mL at 1.35 atm?

devlian [24]

Answer:

$T = 0.182$ Kelvin

Explanation:

As we know that

$PV = nRT\\$

Where P is the pressure in atmospheric pressure

T is the temperature in Kelvin

R is the gas constant

V is the volume in liters

$R = 0.08206$

Substituting the given values in above equation, we get -

$1.35 * \frac{50}{1000}= 4.5 * 0.08206* T\\$

On rearranging, we get

$T = \frac{1.35*50}{1000*0.08206*4.5} \\$

$T = 0.182$ Kelvin

7 0

3 years ago