Answers: 1
Chemistry, 22.06.2019 08:30
Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?
Answers: 1
Chemistry, 22.06.2019 11:40
Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)
Answers: 1
Chemistry, 22.06.2019 16:00
If 15 drops of ethanol from a medical dropper weight 0.60g, how many drops does it takes from a dropper to dispense 1.0ml of ethanol? the density of ethanol is 0.80g/ml
Answers: 1
True or false. the only elements that can be used as fuel in a nuclear power plant are those in whic...
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