Answer :
The atomic mass is the sum of the number of protons and neutrons in the nucleus of an atom.
Explanation :
Atomic number : it is defined as the number of protons or number of electrons.
Atomic number = number of protons = number of electrons
Mass number or atomic mass : It is defined as the sum of the number of protons and the number of neutrons.
Mass number or atomic mass = Number of protons + Number of neutrons
For example :
Number of protons in carbon = 6
Number of neutrons in carbon = 6
Mass number or atomic mass = Number of protons + Number of neutrons
Mass number or atomic mass = 6 + 6
Mass number or atomic mass = 12
Thus, the atomic mass is the sum of the number of protons and neutrons in the nucleus of an atom.
Answer:
6.53g of K₂SO₄
Explanation:
Formula of the compound is K₂SO₄
Given parameters:
Volume of K₂SO₄ = 250mL = 250 x 10⁻³L
= 0.25L
Concentration of K₂SO₄ = 0.15M or 0. 15mol/L
Unknown:
Mass of K₂SO₄ =?
Methods:
We use the mole concept to solve this kind of problem.
>>First, we find the number of moles using the expression below:
Number of moles= concentration x volume
Solving for number of moles:
Number of moles = 0.25 x 01.5
= 0.0375mole
>>Secondly, we use the number of moles to find the mass of K₂SO₄ needed. This can be obtained using the expression below:
Mass(g) = number of moles x molar mass
Solving:
To find the molar mass of K₂SO₄, we must know the atomic mass of each element in the compound. This can be obtained using the periodic table.
For:
K = 39g
S = 32g
O = 16g
Molar mass of K₂SO₄ = (39x2) + 32 + (16x4)
= 78 +32 + 64
= 174g/mol
Using the expression:
Mass(g) = number of moles x molar mass
Mass of K₂SO₄ = 0.0375 x 174 = 6.53g
Answer:
oatmeal with raisins is a heterogeneous mixture. The raisins may be solid, but turn the bowl over and you will see the mixture as a whole most definitely acts like a liquid. Mud puddles are a heterogeneous mixture.
Explanation:
12.04moles
Explanation:
Given parameters:
Number of molecules = 7.25 x 10²⁴molecules
unknown:
Number of moles = ?
Solution:
The moles of a substance is the amount of substance that contains avogadro's number of particles:
1 mole of a substance = 6.02 x 10²³
x moles of the compound will contain: ![\frac{7.25 x 10[tex]^{24}](https://tex.z-dn.net/?f=%5Cfrac%7B7.25%20x%2010%5Btex%5D%5E%7B24%7D)
}{6.02 x 10
}[/tex] = 12.04moles
This gives 12.04moles
Learn more:
Number of moles brainly.com/question/1841136
#learnwithBrainly
Answer:
<h2>1.48 moles</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
We have the final answer as
<h3>1.48 moles</h3>
Hope this helps you
