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Nikolay [14]
3 years ago
15

PLS PLS PLS PLS HELP IM STRUGGLING

Chemistry
1 answer:
andriy [413]3 years ago
5 0

Answer:

A. 4 only

Explanation:

One of the tests for purity is by determining the melting point of a substance. A pure substance has a sharp meting point.

If the solid in question is a pure solid, when it is heated, it will exhibit a sharp melting point. Mixtures however melt over a range of temperatures due to the presence of impurities in the solid.

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How many particles are in a mole? 6.02 × 1023 23 × 106 602 billion 6.02 × 2310
Amanda [17]

Answer:

1mole=6.02x10^{23} unit (Avogadro constant)

Explanation:

It is known by the name of mole (mol) to one of the fundamental physical magnitudes that contemplate the International System of Units. This unit is used to measure the quantity of all kinds of substances present in a given system.

The mole, experts say, reflects the amount of substance that has a specific number of entities of elementary character as atoms can be found in twelve grams of carbon-12. This means that the number of elementary units (as in the case of atoms, molecules or ions, for example) that are reflected in a mole of substance is a constant that has no direct relationship with the type of particle or material in question. This amount is known as Avogadro's number.

This constant, baptized in homage to the scientist of Italian origin Amedeo Avogadro (1776-1856), allows to count microscopic particles from macroscopic measurements (as it is the case of the mass).

6 0
3 years ago
Read 2 more answers
Please help, don't understand this topic
Darya [45]

Answer:

<u><em>Pangaea</em></u>

<u><em>Alfred Wegner</em></u>

<u><em>plate tectonics</em></u>

Explanation:

What did Earth look like 250 million years ago? The continents of Earth were clustered together in formation that a scientist named<em> </em><u>Pangaea</u><u><em>.</em></u>The scientist that named "Pangaea" was a German scientist by the name of <u>Alfred Wegner.</u> He theorized that "Pangaea" split apart and the different landmasses, or continents, drifted to their current locations on the globe. Wegener's theories of plate movement became the basis for the development of the theory of <u>plate tectonics.</u>

8 0
2 years ago
Classify the chemical reaction: 2Al + 3NiSO4 ⟶ Al2(SO4)3 + 3Ni<br> PLEASE HELP!
Anvisha [2.4K]
Following are the types of chemical reactions with a brief overview:

<span>1) Combination (Two elements combine to form a compound)
2) Decomposition (A compound is broken into elements)
3) Single displacement (An element displaces an element present in a compound)
4) Double displacement (The elements of two compounds displace each other)
5) Combustion (Burning Takes places)
<span>6) Redox (Oxidation Reduction Reaction)

If you see the given equation, Al is displacing Ni in the compound NiSO4 and taking its place. Ni is set free as a separate element. So this type of reaction is known as Single Displacement Reaction.</span></span>
8 0
2 years ago
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Select the atomic models that belong to the same element.
iogann1982 [59]
Top left and bottom right are the atomic models of the same element
8 0
2 years ago
What is the difference between an endothermic and an exothermic reaction?
goldenfox [79]

Answer:

Endothermic Reaction:

These type of reactions are those reactions which absorb energy from the surroundings to form products. They also create a cooling effect in the surrounding as they absorb heat and thus the surrounding area gets cooled.

Exothermic Reaction:

These are reactions that release energy,  mostly in the form of heat or light.

The products will release energy there can be a heating effect in the surroundings.

5 0
2 years ago
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