Answer:
c) more OH⁻ ions than H₃O⁺ ions
Explanation:
A substance with a PH of 9 implies that it has more OH⁻ ions than H₃O⁺ ions.
Such substances are said to be an alkaline or a base.
A base is a substance the produces excess hydroxyl ion in aqueous solutions.
An acid will produce excess hydroxonium ions in a solution.
So, the pH scale is used to indicate whether a substance is an acid or base or non of them.
Acids have pH of less than 7
Bases have pH of > 7
Explanation:
Start with a balanced equation.
2H2 + O2 → 2H2O
Assuming that H2 is in excess, multiply the given moles H2O by the mole ratio between O2 and H2O in the balanced equation so that moles H2O cancel.
5 mol H2O × (1 mol O2/2 mol H2O) = 2.5 mol O2
Answer: 2.5 mol O2 are needed to make 5 mol H2O, assuming H2 is in excess.
When two atoms of the same element are covalently bonded, the radius of each atom will be half the distance between the two nuclei because they equally attract the electrons. The reason for this trend is that the bigger the radii, the further the distance between the two nuclei. Hope this helps:)
Answer:
and
Explanation:
All the carbon group atoms, having four valence electrons, form covalent bonds with nonmetal atoms; carbon and silicon cannot lose or gain electrons to form free ions, whereas germanium, tin, and lead do form metallic ions but only with two positive charges
the similarities is that Both carbon and silicon commonly form compounds, easily sharing electrons with other elements. Carbon will make multiple bonds with other carbon molecules by forming single, double and triple covalent bonds. ... Carbon and silicon are often combined, with carbon serving as silicon's backbone.
Answer:
Matter can change state when thermal energy is transferred into or out of the substance. Ice melts and liquid water boils as thermal energy is added. Water vapor condenses and liquid water freezes as thermal energy is removed.