Answer:
Mass = 17.8 g
Explanation:
Given data:
Number of atoms of Ca = 2.68 × 10²³
Mass in gram = ?
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
2.68 × 10²³ atoms × 1 mole /6.022 × 10²³ atoms
0.445 mol
Mass in gram;
Mass = number of moles × molar mass
Mass = 0.445 mol × 40 g/mol
Mass = 17.8 g
Answer:
Reaction rates are not related to spontaneity
Explanation:
A spontaneous reaction is one which occurs on its own or on some activation. Non spontaneous reactions are those which do not occur on their own and thus constant energy must be supplied to make them happen.
Reaction rate is dependent on the amount of reactants and the activation energy and not on the spontaneity of the reaction. Reactions with high activation energy are slow and reactions with low activation energy are fast.
One mole (abbreviated mol) is equal to 6.022×1023 molecular entities (Avogadro's number), and each element has a different molar mass depending on the weight of 6.022×1023 of its atoms (1 mole). The molar mass of any element can be determined by finding the atomic mass of the element on the periodic table.
Water vapor is moisture in the air or humidity, they results from the evaporation of water, it also traps heat, and condenses to make clouds. Water vapor is water in its gaseous state instead of liquid or solid . It is extremely important to the weather and climate.
Answer:
<h2>1. high</h2><h2>2. low</h2>
Explanation:
Iodine is an important and essential element or nutrient of the diet that has many important roles in the body of human beings and some other organisms. When the deficiency of the iodine takes place in the diet or overall in the body then such type of the deficiency is called dietary iodine deficiency that leads to the high level of the TSH of the plasma and thus the thyroxine level decreases or becomes low. Iodine deficiency causes goiter and some other metabolic processes in the body.
