Which of the following is the most important, when working in the science laboratory?

Which chemical equation is balanced?

Lilit [14]

I think the answer is <span>PCl5 + 4H2O → 5HCl + H3PO4
</span>

7 0

2 years ago

Read 2 more answers

Which substance can not be decomposed by a chemical change?

slamgirl [31]

The answer is (2) Copper. Because copper is consist of atom. If it is decomposed, the atom will be changed. While chemical change is just the break down and form of chemical bonds between atoms.

6 0

2 years ago

The force of 20 N acts upon a 5kg block. What is the acceleration of the block?

charle [14.2K]

Answer:

<h2>The answer is 4 m/s²</h2>

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

$a = \frac{f}{m} \\$

where

a is the acceleration

f is the force

m is the mass

From the question

f = 20 N

m = 5 kg

We have

$a = \frac{20}{5} \\$

We have the final answer as

Hope this helps you

8 0

2 years ago

To find the atomic mass of a particular atom you need to know

AveGali [126]

The answer is (C) as the definitions states that atomic mass is the number of protons and neutrons.
Hope this helps :).

6 0

2 years ago

What type of chemical bond holds the na+ and cl- ions together in table salt?

fredd [130]

<em>The bond between Na + and Cl- ions is an ionic bond</em>

<em>To achieve stability, atoms with low ionization energy such as Na atoms will release electrons and bind to atoms with high-affinity energy such as Cl atoms</em>

$\boxed{\boxed{\bold{Further~explanation}}}$

Atoms have different stability. Unstable atomic atoms will try to form stable electron configurations like those of noble gases. Where noble gases have the number of outer electrons 2 or 8

The formation of electron configurations such as noble gases can be done by forming shared ions or electron pairs

Atoms with high ionization energy and atoms that are difficult to draw electrons will form bonds with shared electron pairs (electrons can be from one atom or two atoms attached)

In forming ions, atoms will release or attract electrons

Ion bonds occur because atoms that have low ionization energy (easily release electrons) form a + ion, and these electrons are bound by atoms that have large affinity energy (easily pulling electrons)

Generally, ionic bonds occur in metal and nonmetallic elements. Metal elements have low ionization energy and non-metallic elements have a high electron affinity

In Na atoms, to achieve stability, Na will release one electron so that it has an electron configuration like noble gas Ne

Na: 2 8 1

Ne: 2 8

so that it becomes a Na + ion

While the Cl atom will bind one electron, so it has an electron configuration like noble gas Ar

Cl: 2 8 7

Ar: 2 8 8

So that it becomes a Cl- ion

Finally, there will be an attractive attraction between positive ions and negative ions and NaCl is formed

So the bond between Na + and Cl- ions is an ionic bond

$\boxed{\boxed{\bold{Learn~more}}}$