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max2010maxim [7]
3 years ago
13

Why didn't mendeleev use atomic number to arrange the elements?

Chemistry
1 answer:
Pepsi [2]3 years ago
8 0

The primary reason for this was that Mendeleev didn't know that atomic numbers actually existed. Atomic numbers were only discovered a period after Mendeleev's time. The use of X-rays made it possible to find the atomic number, and those had not been discovered yet. <span>
<span>The periodic table was then arranged in 1913 by Henry Moseley in an arrangement according to atomic number.</span></span>

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Answer:

b. 2.28 M

Explanation:

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<em>Where 2 moles of NaOH react per mole of H2SO4</em>

<em />

To solve the concentration of NaOH we need to find the moles of H2SO4. Using the chemical equation we can find the moles of NaOH that react and with the volume the molar concentration as follows:

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<h3>b. 2.28 M</h3>
7 0
3 years ago
PLEASE HELP! I'll mark brainliest!
OLEGan [10]
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What is the concentration of OH– ions at a pH = 8?pH+pOH=148+pOH=14pOH=6
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What is the ratio of H+ ions to OH– ions at a pH = 2?The ratio is 0.00000001:0.000001 which is equal to 0.01
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