Answer:
One valence electrons and are the most reactive.
Explanation:they are the alkali metals.
Molarity is defined as the number of moles of solute in volume of 1 L solution.
the molarity of KOH solution to be prepared is 0.500 M
the volume of solution to be prepared is 250 mL
the number of KOH moles in 1 L - 0.500 mol
therefore number of KOH moles in 250 mL - 0.500 mol/L x 0.250 L = 0.125 mol
Mass of KOH in 0.125 mol - 0.125 mol x 56.10 g/mol = 7.01 g
The mass of KOH required to make the solution is therefore 7.01 g
Answer: The difference between a physical reaction and a chemical reaction is composition. In a chemical reaction, there is a change in the composition of the substances in question; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition.
Explanation:
the correct answer would be C. All matter is made up of molecule because gas is one matter and solid is one matter and water and ice/liquid and solid is not hard to see, so the correct answer would be C. All matter is made up of molecule.
Answer:
pH = 3 (though the option is missing)
Explanation:
We have a solution with a concentration of the hydrogen ion, [H⁺] = 0.001 mol/L = 0.001 M. We can calculate the pH using its definition.
pH = -log [H⁺]
pH = -log 0.001
pH = 3
Since the pH < 7, the solution is acid. Other way to recognize that a solution is acid is when [H⁺] > 10⁻⁷ M at 25°C.
