What is Determine the mass of 2.40 moles of CoH12

25 POINTS! Will mark brainliest if you have a good response!

Zolol [24]

Electrons uniting with electrons of another atom is the cause in this relationship. The effect is a chemical change.

6 0

3 years ago

Write the appropriate symbol for each of the following isotopes: (a) Z 74, A 186; (b) Z 80, A 201; (c) Z 34, A 76; (d) Z 94, A 2

beks73 [17]

Answer: a) $_{74}^{186}\textrm{W}$

b) $_{80}^{201}\textrm{Hg}$

c) $_{34}^{76}\textrm{Se}$

d) $_{94}^{239}\textrm{Pu}$

Explanation:

General representation of an element is given as:_Z^A\textrm{X}

where,

Z represents Atomic number

A represents Mass number

X represents the symbol of an element

Mass number is defined as the sum of number of protons and neutrons that are present in an atom.

Mass number = Number of protons + Number of neutrons

In an atom, when neutrons or protons are lost or gains, it directly affects the mass number of an atom.

Atomic number is defined as the number of protons or number of electrons that are present in an atom.

It is characteristic of a particular element.

Atomic number = Number of electrons = Number of proton

a) Z 74, A 186: $_{74}^{186}\textrm{W}$

b) Z 80, A 201: $_{80}^{201}\textrm{Hg}$

c) Z 34, A 76: $_{34}^{76}\textrm{Se}$

d) Z 94, A 239.: $_{94}^{239}\textrm{Pu}$

6 0

3 years ago

How do you use the changes in the phase of water to keep you cool?

sineoko [7]

Answer:

by freezing

Explanation:

8 0

3 years ago

What do Potassium and Krypton have in common and what are their differences based on their location on the periodic table?

Kamila [148]

Potassium (K) and Krypton (Kr) are in the same period, so they have the same number of electron shells. Potassium is more reactive than Krypton because it only has one valence electron.

K and Kr are both in Period 4, so they each have the n = 1, 2, 3, and 4 shells. Kr is less reactive than K because it already has a complete octet.

“Potassium (K) and Krypton (Kr) are in the same period, so they have the same number of electron shells. Krypton is more reactive than Potassium because it has a full outer shell” is incorrect because having a full outer shell means that the element is unreactive.

“Potassium (K) and Krypton (Kr) are in the same group, so they have the same number of valence electrons. They have different numbers of electron shells” is incorrect for three reasons:

1. K is in Group 1 and Kr is in Group 18.

2. K has one valence electron, and Kr has eight valence electrons.

3. They have the same number of electron shells.

“Potassium (K) and Krypton (Kr) are in the same group, so they have the same number of valence electrons. They have different numbers of electron shells” is incorrect for two reasons:

1. K and Kr have different numbers of valence electrons.

2. They have the same number of electron shells.

8 0

3 years ago

The most important part of the brain for an organism is the...

Serjik [45]

Answer:

its the lower brainstem

Explanation:

The lowest part of the brainstem, the medulla is the most vital part of the entire brain and contains important control centers for the heart and lungs.

4 0

2 years ago

What is Determine the mass of 2.40 moles of CoH12​

What is Determine the mass of 2.40 moles of CoH12