Answer:
5.0 × 10²⁴ molecules
Explanation:
Step 1: Write the balanced double displacement reaction
2 NaOH + CuSO₄ ⇒ Na₂SO₄ + Cu(OH)₂
Step 2: Calculate the moles corresponding to 5.0 × 10²⁴ molecules of Na₂SO₄
We will use Avogadro's number: there are 6.02 × 10²³ molecules in 1 mole of molecules.
5.0 × 10²⁴ molecule × 1 mol/6.02 × 10²³ molecule = 8.3 mol
Step 3: Calculate the moles of CuSO₄ required to produce 8.3 moles of Na₂SO₄
The molar ratio of CuSO₄ to Na₂SO₄ is 1:1. The moles of CuSO₄ required are 1/1 × 8.3 mol = 8.3 mol.
Step 4: Calculate the molecules corresponding to 8.3 moles of CuSO₄
We will use Avogadro's number.
8.3 mol × 6.02 × 10²³ molecule/1 mol = 5.0 × 10²⁴ molecule
Mole fraction<span> is another way of expressing the concentration of a solution or mixture. It is equal to the </span>moles<span> of one component divided by the total </span><span>moles.
mass CH4O = 0.270 (51) = 13.77 g methanol
water = 51 - 13.77 = 37.23 g water
Hope this answers the question. Have a nice day.</span>
The patch area in square kilometers is 1.59*10⁻⁹ km₂
Why?
This is an unit conversion problem. We have to convert from cm² to km². We can do that by knowing that there are 100 cm in 1 m, and 1000 m in 1 km, so 100000 cm=1km. Knowing that we can apply the following conversion factor:

Now to convert this value to scientific notation, we have to move the decimal point to the right until we get a whole number, and the exponent of the number 10 is going to be the number of spaces we moved to the right (negative), so the final answer is:

Have a nice day!
#LearnwithBrainly
In 1770 a Scottish physician and Chemist Daniel Rutherford performed a simple experiment with which he discovered nitrogen. Rutherford being with an empty bottle that he turned upside down in a pan of water so that the air was trapped. A buring candle was placed inside the bottle with the trapped air causing the water to rise a bit. The part of the air that seemed to "disappear" when the candle was bured was oxygen gas and the part of the air that did not "disappear" Ruthford discovered Nitrogen.
Answer:742 torr= approximately 0.976 atm
Explanation:
Since we know that one atm= 760 torr, we can compute the following calculation:
(742 torr/1)*(1atm/760torr)=0.976316 atm
Remember sig figs (3) to round it to 0.976 atm
*
=0.976316=0.976 atm
(torr cancels out and we're left with atm)
Hope this helps :)