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An atom of 26Mg contains ________ neutrons.

You may have heard that mixing household bleach with household ammonia is dangerous, this is true! Many different reactions can occur when these are mixed, almost all of them bad. One of these is shown below, where sodium hypochlorite, NaOCl (in bleach), reacts with ammonia, NH3, to give NaCl and H2O (which are harmless), and hydrazine, N2H4, which is toxic. NaOCl + NH3 → NaCl + H2O + N2H4 What is the balanced version of this equation?

A study is measuring the effect of a new drug to treat Alzheimer’s disease. One group of patients is taking the drug and the other is taking a placebo. All participants have their beta amyloid levels measured after the study. Which statistical test is best to test for any change?

What is the maximum amount in grams of  that can be produced by the reaction of 1.0 g of S with 1.0 g of  via the equation below?  

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