There are three perfect squares in a standard die; 1, 2, 4. If there is two standard dies, then the probability of getting a perfect square is 1/3 x 1/3 = 1/9.
There are 4 numbers less than 5 in a standard die, making it 1/4 x 1/4=1/16.
Answer:
The correct option is;
It contains 6.02 × 10²³ particles of a given substance
Explanation:
A mole of substance is the standard scientific unit of measurement for the quantity of the substance which is made up of a large number of small particles such as molecules, ions, atoms, electrons or other entities.
The General Conference on Weights and Measures defines the mole as the amount of a substance that contains 6.02214076 × 10²³ units of entities
The number 6.02214076 × 10²³, is also known as Avogadro's number.
Answer:
A chemical formula for a molecular compound represents the composition of <u><em>a molecule.</em></u>
Explanation:
Chemical formulas are alphanumeric expressions that are used to indicate the composition of chemical substances. They consist of chemical symbols that indicate the elements that form a compound; The number of atoms provided by each element is also indicated by the use of a subscript, that is, a small number that is placed below and to the right of each element that so requires. When an element does not have a subscript, it is understood that there is only one atom of it in the substance.
Each molecule corresponds to a chemical formula, as well as a name according to the rules of the chemical nomenclature.
Then, <u><em>a chemical formula for a molecular compound represents the composition of a molecule.</em></u>
The law of conservation of mass dictates that the total mass of reactants must be equal to the total mass of the products. Thus:
mass(MgO) = mass(Mg) + mass(O)
mass(MgO) = 24 + 16
mass(MgO) = 40 g
The third option is correct.
Asteroids come from the asteroid belt