Answer:
Electrons- 95
Protons- 95
Neutrons-146
Explanation:
An atoms is made up of three fundamental particles; electrons, protons and neutrons,
Americium belongs to the f block in the periodic table. It is an actinide element.
An atom of Am-241 contains 95 protons, 95 electrons and 146 neutrons.
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 : The correct option is, (b) occur when there is more free energy in the reactants than the products.
Explanation :
Endergonic reactions : It i defined as the reaction in which the energy is absorbed during the reaction.
In endergonic reactions, the Gibbs free energy of product is lower than the reactants. That means, ΔG > 0 and the reaction is non-spontaneous.
Exergonic reactions : It i defined as the reaction in which the energy is released during the reaction.
In exergonic reactions, the Gibbs free energy of product is greater than the reactants. That means, ΔG < 0 and the reaction is spontaneous.
Hence, the endergonic reactions is occur when there is more free energy in the reactants than the products.
The products lie on the right hand side of the equation. So, in this case, they are:
S and O₂
The answer is C.
