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3 years ago

List one reason as to why historical growth has slowed in recent years.

Chemistry

1 answer:

hodyreva [135]3 years ago

4 0

Lower fertility and longer lifespans steadily increased the potential labor force relative to the total population

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Aqueous hydrochloric acid (HCl) reacts with solid sodium hydroxide (NaOH) to produce aqueous sodium chloride (NaCl) and liquid w

Naddika [18.5K]

Answer:

87.9 % is the percent yield of H₂O

Explanation:

This is the neutralization reaction. A base reacts with an acid to produce water and the correspondly ionic salt.

NaOH + HCl → NaCl + H₂O

As we have the mass of the two reactants, we must determine the limiting reactant.

Let's convert to moles, the mass of each reactant. (mass / molar mass)

21.1 g / 36.45 g/mol = 0.579 moles of HCl

46.3 g / 40g/mol = 1.15 moles of NaOH

Ratio is 1:1, so it is obviously that the limiting reactant is the HCl. For 1.15 moles of NaOH, i need the same amount of acid, but I only have 0.579 moles

Let's work with the products now. Ratio is 1:1 again, so If I have 0.579 moles of acid, I can produce 0.579 moles of H₂O.

How many grams are 0.579 moles of water? We should find it out as this

mol . molar mass = mass → 0.579 mol . 18 g/mol = 10.4 g

We were told that the production of water was 9.17 g, so let's determine the percent yield as this:

(Yield produced / Theoretical yield) . 100 =

(9.17 g / 10.4g ) . 100 = 87.9 %

6 0

4 years ago

In the reaction of silver nitrate with copper metal, metallic silver comes out of solution, and the solution turns blue. This as

nlexa [21]

In the reaction of silver nitrate with copper metal, metallic silver comes out of solution, and the solution turns blue. This as a <u>single replacement</u> reaction.

<h3>What is single replacement reaction?</h3>

A single replacement reaction, also known as a single displacement reaction, occurs when one element in a molecule is swapped out for another. The starting materials are always pure elements, such as a pure zinc metal or hydrogen gas, plus an aqueous compound.

A + BC → B + AC

When A is more reactive than B or when the product AC is more stable than BC, single replacement reactions happen. A and B could either be two halogens or two metals (with hydrogen included) (C is a cation). C functions as a spectator ion when BC and AC are in aqueous solutions.

For example, 2HCl(aq)+Zn(s)→ZnCl₂(aq)+H₂(g)

Learn more about single replacement reactions here:

brainly.com/question/19068047

#SPJ4

8 0

2 years ago

consider the substance:carbon dioxide, gold, bronze, alcohol, iron, and, oxygen.from the list , select the substances that :(1)

lbvjy [14]

Answer:

Oxygen

Explanation:

· Air decolorization makes use of chromophores’ instability on oxygen to decolorize the oil by air-oxidizing pigments. For example, the carotenoid and chlorophyll in the oil are very unstable because of their structure, which is easy to be discolored under the action of oxygen. However, air decolorization leads to thermal oxidation of the oil, too.

5 0

3 years ago

Help for brainliest

Margarita [4]

Answer:

those things that looks like cristals

8 0

3 years ago

1. Mg2+ and Ca2+ are in the same group on the periodic table. In terms of electronic

finlep [7]

Answer:

Se detailed explanation.

Explanation:

Hello,

In this case, since both magnesium and calcium ions are in group IIA, we can review the following similar properties:

- Since both calcium and magnesium are in group IIA they have two valence electrons, it means that the both of them have two electrons at their outer shells.

- They are highly soluble in water when forming ionic bonds with nonmetals such as those belonging to halogens and oxygen's family.

- Calcium has 18 electrons and magnesium 10 which are two less than the total protons (20 and 12 respectively) since the both of them have lost two electrons due their ionized form.

- Their electron configurations are:

$Ca^{20}=1s^2,2s^2,2p^6,3s^3,3p^6,4s^2\\\\Mg^{12}=1s^2,2s^2,2p^6,3s^2$

It means that the both of them are at the $s$ region since it is the last subshell at which their electrons are.

Best regards.

8 0

3 years ago