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A balloon is filled with hydrogen gas to a volume of 3 liters, which corresponds to roughly 6 moles of hydrogen atoms (We will soon see that elemental hydrogen exists as a molecule, but that doesn’t change anything in this problem). What is the weight of hydrogen in the balloon?

Water electrolysis can be catalyzed by acid or by base. When catalyzed by acid, the overall redox reaction is shown below (in the box) 2 H2O(l) + 4 H+(aq)  →  2 H2(g) + O2(g) + 4 H+(aq)   In the overall redox reaction equation: 2 H2O(l) + 4 H+(aq)  →  2 H2(g) + O2(g) + 4 H+(aq), also shown above, which species is the catalyst?

There is roughly 6g of copper in every iPhone. How many moles of copper is this?

Which of the following hormone levels is higher in women than men at rest?

     An ethanol flame in a large water bottle, a classic chemistry demonstration The balanced equation for the combustion of ethanol in oxygen gas is: CH3CH2OH(l) + 3O2(g) → 2CO2(g) + 3H2O(g) If 1 mole of ethanol (CH3CH2OH) is burned, how many grams of carbon dioxide (CO2) are produced (to the nearest whole number)? Assume that ethanol is the limiting reagent. Assume the average atomic weight of C is 12.011 g/mol Assume the average atomic weight of O is 15.999 g/mol

Patients with hypophosphatemia (low blood phosphate) can be treated with intravenous Sodium Phosphate solution. A Lewis structure for sodium dihydrogen phosphate is shown below, without nonbonding electrons for clarity. Typically, 500 mg of sodium phosphate would be administered in 100 mL of solution. What is the concentration of sodium phosphate in this solution, in M? The average atomic weight of sodium is 22.990 g/mol The average atomic weight of phosphorus is 30.974 g/mol The average atomic weight of oxygen is 15.999 g/mol The average atomic weight of hydrogen is 1.008 g/mol

Acetic acid is among the top 10 chemicals manufactured in the U.S. each year. Most of the acetic acid is used to make vinyl acetate, which is turn is used to make polyvinyl acetate, which has a myriad of industrial uses, glue being one of them. The boiling point of acetic acid is 118°C. The thermal energy at this temperature is around 3.3 kJ./mol.Acetic acid tends to exist as two molecules that are held together by hydrogen bonds, as shown in the image.When acetic acid boils, which of the bonds indicated in the image as A and B is the thermal energy primarily used to break?

An ion has 12 protons, 14 neutrons, and 10 electrons. The symbol for the ion is

The net ionic equation for the reaction between aqueous solutions of HF and KOH is ________.

The concentration (M) of an aqueous methanol produced when 0.200 L of a 2.00 M solution was diluted to 0.800 L is ________.