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2 years ago

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Chemistry

1 answer:

snow_tiger [21]2 years ago

5 0

Compounds are formed when two or more <u>elements</u> are chemically combined.
When these elements are <u>chemically</u> combined, a new substance is formed with new chemical and physical <u>properties</u>.
An element is a <u>pure</u> substance that cannot be separated into simpler substances by <u>physical</u> or chemical means.
A compound is two or more elements <u>combined</u> chemically to produce a new substance.
When two or more elements chemically combine, the compound has new properties, different from the chemical and physical properties of the <u>original</u> elements.

<h3>What is a chemical element?</h3>

A chemical element can be defined as a pure substance which comprises atoms that have the same atomic number (number of protons) in its nuclei and as such it is the primary constituent of matter.

Generally, some examples of a chemical element include the following:

Argon.
Sodium.
Carbon.
Oxygen.
Hydrogen.
Phosphorus
Copper
Aluminum
Potassium
Magnesium

<h3>What is a pure substance?</h3>

A pure substance can be defined as a single sample of matter that cannot be separated into other kinds of matter through the use of any physical or chemical separating technique because it has distinct chemical properties and a definite and constant composition.

Read more on pure substances here: brainly.com/question/2056940

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miss Akunina [59]

Answer:

$\boxed{\text{40 mol Al}}$

Explanation:

Al₂O₃ ⟶ 2Al + 3O₂

n/mol: 20

$\text{Moles of Al} = \text{20 mol Al$_{2}$O$_{3}$}\times \dfrac{\text{2 mol Al}}{\text{1 mol Al$_{2}$O$_{3}$}}= \textbf{40 mol Al}\\\text{You can produce }\boxed{\textbf{40 mol Al}}$

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If 56.8 ml of bacl2 solution is needed to precipitate all the sulfate ion in a 554 mg sample of na2so4 (forming baso4), what is

IrinaVladis [17]

<span>0.0687 m The balanced equation is BaCl2 + Na2SO4 ==> BaSO4 + 2 NaCl Looking at the equation, it indicates that there's a 1 to 1 ratio of BaCl2 and Na2SO4 in the reaction. So the number of moles of each will be equal. Now calculate the number of moles of Na2SO4 we had. Start by looking up atomic weights. Atomic weight sodium = 22.989769 Atomic weight sulfur = 32.065 Atomic weight oxygen = 15.999 Molar mass Na2SO4 = 2 * 22.989769 + 32.065 + 4 * 15.999 = 142.040538 g/mol Moles Na2SO4 = 0.554 g / 142.040538 g/mol = 0.003900295 mol Molarity is defined as moles per liter, so let's do the division. 0.003900295 mol / 0.0568 l = 0.068667165 mol/l = 0.068667165 m Rounding to 3 significant figures gives 0.0687 m</span>

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nydimaria [60]

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~ I hope this helped, and I would appreciate Brainliest. ♡ ~ ( I request this to all the lengthy answers I give ! )

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3 years ago

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symbol = Au
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<u>answer: E</u>

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