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3 years ago

What makes up nearly all of the atom's mass?

Chemistry

2 answers:

VMariaS [17]3 years ago

7 0

Sum of the number of protons and neutrons, which is the nucleus

Ber [7]3 years ago

5 0

Answer:

The Nucleus

Explanation:

The nucleus of an atom contains both the protons (positively charged particles) and the neutrons (particles with no charge) - these two set of particles present in the nucleus of an atom determines the mass of an atom. Hence, atomic mass is the sum of the number of protons and number of neutrons present in the nucleus of an atom.

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What is the formula of the compound formed between the potassium ion and the sulfide ion?

KIM [24]

The formula for K+ and S-2 is K2S because you need 2 potassium ions to balance out the sulfide ion

4 0

3 years ago

A chemical processing plant has a network of pipes that are used to transfer liquid chemicalproducts from one part of the plant

liq [111]

Answer:

Explanationis the long-distance transportation of a liquid or gas through a system of pipes—a pipeline—typically to a market area for consumption. The latest data from 2014 gives a total of slightly less than 2,175,000 miles (3,500,000 km) of pipeline in 120 countries of the world.[1] The United States had 65%, Russia had 8%, and Canada had 3%, thus 75% of all pipeline were in these three countries.[1]

Pipeline and Gas Journal's worldwide survey figures indicate that 118,623 miles (190,905 km) of pipelines are planned and under construction. Of these, 88,976 miles (143,193 km) represent projects in the planning and design phase; 29,647 miles (47,712 km) reflect pipelines in various stages of construction. Liquids and gases are transported in pipelines and any chemically stable substance can be sent through a pipeline.[2] Pipelines exist for the transport of crude and refined petroleum, fuels – such as oil, natural gas and biofuels – and other fluids including sewage, slurry, water, beer, hot water or steam for shorter distances. Pipelines are useful for transporting water for drinking or irrigation over long distances when it needs to move over hills, or where canals or channels are poor choices due to considerations of evaporation, pollution, or environmental impact.:

7 0

3 years ago

There are two steps in the usual industrial preparation of acrylic acid, the immediate precursor of several useful plastics. In

qaws [65]

The question is incomplete, here is the complete question:

There are two steps in the usual industrial preparation of acrylic acid, the immediate precursor of several useful plastics. In the first step, calcium carbide and water react to form acetylene and calcium hydroxide:

$CaC_2(s)+2H_2O(g)\rightarrow C_2H_2(g)+Ca(OH)_2(s)$

In the second step, acetylene, carbon dioxide and water react to form acrylic acid:

$6C_2H_2(g)+3CO_2(g)+4H_2O(g)\rightarrow 5CH_2CHCO_2H(g)$

Write the net chemical equation for the production of acrylic acid from calcium carbide, water and carbon dioxide. Be sure your equation is balanced.

Answer: The net chemical equation is written below.

Explanation:

The intermediate balanced chemical reaction are:

(1) $CaC_2(s)+2H_2O(g)\rightarrow C_2H_2(g)+Ca(OH)_2(s)$ ( × 6 )

(2) $6C_2H_2(g)+3CO_2(g)+4H_2O(g)\rightarrow 5CH_2CHCO_2H(g)$

To omit acetylene from the net chemical reaction, we multiply Equation (1) by 6.

Equation 1: $6CaC_2(s)+12H_2O(g)\rightarrow 6C_2H_2(g)+6Ca(OH)_2(s)$

Equation 2: $6C_2H_2(g)+3CO_2(g)+4H_2O(g)\rightarrow 5CH_2CHCO_2H(g)$

Net chemical equation: $6CaC_2(s)+3CO_2(g)+16H_2O(g)\rightarrow 5CH_2CHCO_2H(g)+6Ca(OH)_2(s)$

Hence, the net chemical equation is written above.

6 0

3 years ago

In a 0.730 M solution, a weak acid is 12.5% dissociated. Calculate Ka of the acid.

Mamont248 [21]

Answer:

Approximately $1.30 \times 10^{-2}$ , assuming that this acid is monoprotic.

Explanation:

Assume that this acid is monoprotic. Let $\rm HA$ denote this acid.

$\rm HA \rightleftharpoons H^{+} + A^{-}$ .

Initial concentration of $\rm HA$ without any dissociation:

$[{\rm HA}] = 0.730\; \rm mol \cdot L^{-1}$ .

After $12.5\%$ of that was dissociated, the concentration of both $\rm H^{+}$ and $\rm A^{-}$ (conjugate base of this acid) would become:

$12.5\% \times 0.730\; \rm mol \cdot L^{-1} = 0.09125\; \rm mol \cdot L^{-1}$ .

Concentration of $\rm HA$ in the solution after dissociation:

$(1 - 12.5\%) \times 0.730\; \rm mol \cdot L^{-1} = 0.63875\; \rm mol\cdot L^{-1}$ .

Let $[{\rm HA}]$ , $[{\rm H}^{+}]$ , and $[{\rm A}^{-}]$ denote the concentration (in $\rm mol \cdot L^{-1}$ or $\rm M$ ) of the corresponding species at equilibrium. Calculate the acid dissociation constant $K_{\rm a}$ for $\rm HA$ , under the assumption that this acid is monoprotic:

$\begin{aligned}K_{\rm a} &= \frac{[{\rm H}^{+}] \cdot [{\rm A}^{-}]}{[{\rm HA}]} \\ &= \frac{(0.09125\; \rm mol \cdot L^{-1}) \times (0.09125\; \rm mol \cdot L^{-1})}{0.63875\; \rm mol \cdot L^{-1}}\\[0.5em]&\approx 1.30 \times 10^{-2} \end{aligned}$ .

5 0

3 years ago

What was the Copernican revolution?

Zolol [24]

The Copernican revolution is about the model of the solar system and was given by a polish astronomer. Option C. The discovery that the universe was expanding.

The Copernican Revolution become the paradigm shift from the Ptolemaic model of the heavens, which described the cosmos as having Earth stationery on the center of the universe, to the heliocentric version with the solar on the center of the solar system.

Copernican Revolution, shift the subject of astronomy from a geocentric understanding of the universe, focused around Earth, to heliocentric knowledge, concentrated across the sun, as articulated by the Polish astronomer Nicolaus Copernicus.

This revolution changed the way of thinking of the solar system. Earlier it was thought that earth is in the center of the solar sysytem,i.e; people believed in the geocentric model, but according to Copernicus the solar system has the sun at the center and the remaining planets revolve around it i.e he believed in a heliocentric model.

Learn more about the Copernican revolution here:-brainly.com/question/11385060

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4 0

2 years ago