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According the balanced equation for the combustion reaction of butane (C4H10) below, how many grams of water can be produced when 1.25 g of butane (C4H10) are burned in a butane lighter. Assume excess oxygen is present. Show the calculation.                              2 C4H10 (g) + 13 O2 (g) → 8 CO2 (g) + 10 H2O (l)                                                                                                                                         

Which of the following are conjugate acid-base pairs in the acid-base reaction between ethanamine (CH3CH2NH2) and water?           CH3CH2NH2 (aq) + H2O (l) ⇋ CH3CH2NH3+ (aq) + OH– (aq)    I. H2O and CH3CH2NH2 II.  H2O and OH– III. CH3CH2NH2 and CH3CH2NH3+ IV. CH3CH2NH3+ and OH–

When magnesium chloride dissolves in water, it forms _______ with water molecules.

Which of the following statements BEST describes what happens when an acid reacts with water? The acid donates a proton. Water donates a proton. Water acts as a base. Hydronium ion is formed. Hydroxide ion is formed.

What is the [H3O+] in a solution that has a [OH–] of 3.2 × 10–4 mol/L?

What is the pH of a solution with a [H3O+] of 7.9 × 10–11 mol/L?

Alpha activity has a frequency of ____ to ___

Stage N2 ends when:

A negative sharp wave followed by a positive component is a ___________.

Stage N2 begins with: