Answer:
I believe the answer isT 2.
Explanation:
he formula for IMA of a first-class lever is effort-distance/resistance-distance.
First we calculate the concentration of HCl:
Moles = mass / Mr
= 25 / 36.5
= 0.685 mol
Concentration = 0.685/1.5 = 0.457 mol / dm³
For a strong monoprotic acid, the concentration of hydrogen ions is equal to the acid concentration.
pH = -log[H+]
pH = -log(0.457)
= 0.34
94.6 g. You must use 94.6 g of 92.5 % H_2SO_4 to make 250 g of 35.0 % H_2SO_4.
We can use a version of the <em>dilution formula</em>
<em>m</em>_1<em>C</em>_1 = <em>m</em>_2<em>C</em>_2
where
<em>m</em> represents the mass and
<em>C</em> represents the percent concentrations
We can rearrange the formula to get
<em>m</em>_2= <em>m</em>_1 × (<em>C</em>_1/<em>C</em>_2)
<em>m</em>_1 = 250 g; <em>C</em>_1 = 35.0 %
<em>m</em>_2 = ?; _____<em>C</em>_2 = 92.5 %
∴ <em>m</em>_2 = 250 g × (35.0 %/92.5 %) = 94.6 g
Answer:
This question is incomplete, the complete question is:
Nancy and Hiyang are training for a race. They entered some of their training notes in a chart. Which information should be added to the chart in order find out who ran a greater distance?
The answer is C). the units used to measure distance each day
Explanation:
According to the question, Nancy and Hiyang are training for a race that involves them recording the distance they ran in a chart. Distance, as a quantity, is measured using different S.I units like metres, kilometers, miles, centimeters, etc.
However, in order to accurately discover whether Nancy or Hiyang ran a greater distance as recorded in their chart, the units used to measure distance each day must be included. This is because the unit of a quantity determines how big or small it is in comparison to another. For example, 20metres is not the same as 20centimetres.
If the unit they used in measuring their distance is not included, it will be impossible to tell what is being measured, talkless of who ran a greater distance
<h3>
Answer:</h3>
2.47 × 10^24 molecules
<h3>
Explanation:</h3>
One mole of a compound contains molecules equivalent to the Avogadro's number, 6.022 × 10^23.
That is, 1 mole of a compound = 6.022 × 10^23 molecules
Therefore,
1 mole of Na₂CO₃ = 6.022 × 10^23 molecules
Thus, we can calculate the number of molecules in 4.1 moles of Na₂CO₃
we get,
= 4.1 moles × 6.022 × 10^23 molecules
= 2.47 × 10^24 molecules
Hence, 4.1 moles of Na₂CO₃ contains 2.47 × 10^24 molecules
