Option 1/A (It is the first one)
They have the same number of electrons in their outer shells. Elements in the same group often share similar chemical properties because the outer electrons generally determine a lot of their properties
Answer:
7.5 g of hydrogen gas reacts with 50.0 g oxygen gas to form 57.5 g of water.
Explanation:
Here we have the check if the mass of the reactants is equal to the mass of the products.
Reactants

Products

The data is consistent with the law of conservation of matter.
Reactants

Products

The data is not consistent with the law of conservation of matter.
Reactant

Products

The data is not consistent with the law of conservation of matter.
Only the first data is consistent with the law of conservation of matter.
Answer:
A, C and D are correct.
Explanation:
Hello.
In this case, since the relationship between the vapor pressure of a solution is directly proportional to the mole fraction of the solvent and the vapor pressure of the pure solvent as stated by the Raoult's law:

Since the solute is not volatile, the mole fraction of the solute is not taken into account for vapor pressure of the solution, therefore A is correct whereas B is incorrect.
Moreover, since the higher the vapor pressure, the weaker the intermolecular forces due to the fact that less more molecules are like to change from liquid to vapor and therefore more energy is required for such change, we can evidence that both C and D are correct.
Best regards.
In 1 molecule of the compound C₆H₁₂O₂ there are 12 moles of hydrogen atoms
<h3>Further explanation</h3>
Given
C₆H₁₂O₂ compound
Required
moles of Hydrogen
Solution
In a compound, there is a mole ratio of the constituent elements.
The empirical formula is the smallest comparison of atoms of compound forming elements.
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
In the C₆H₁₂O₂ compound, there are 3 forming elements: C, H and O
The number of each element is indicated by its subscript
C: 6 moles
H = 12 moles
O = 2 moles