Knotty NotationMath brain teasers require computations to solve.
A single drop of water contains 1.70 quintillion molecules. In the chemistry lab, I'm following a procedure that calls for me to add 30 drops of water to a solution. I must report how many hydrogen atoms I have added to the solution. I must write the answer in scientific notation.
What should I report?
HintConsult a dictionary or a chemistry text.
AnswerI should report that I have added 1.02*10^20 hydrogen atoms to the solution.
I have added 30 drops of water. Each drop of water contains 1.7 quintillion molecules. So, I have added 51 quintillion molecules (1.7*30=51). Since each molecule of water has 2 hydrogen atoms, you can determine that I have added 102 quintillion hydrogen atoms to the solution (2*51 = 102).
Also, 1 quintillion is equal to 1 followed by 18 zeros. In scientific notation, it's written as 1*10^18. In scientific notation, a number is expressed as a decimal number between 1 and 10 multiplied by a power of 10. So, in scientific notation, 102 quintillion = 1.02*10^20.
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