Answer:- The volume of copper is 280 mL.
Solution:- Density and mass of copper metal are given and it asks to calculate the volume of it.
Density is directly proportional to mass and inversely proportional to the volume. The density formula is:

where D stands for density, M stands for mass and V stands for volume.
Since, the problem asks to calculate the volume, let's rearrange the formula for volume.

The given density is 8.9 grams per mL and the mass is 2.5 kg. We need to convert the mass unit from kg to g so that the g unit could be canceled while calculating volume.
The conversion factor is, 1kg = 1000g

= 2500g
Let's plug in the values in the density formula to calculate the volume.

= 280.89 mL
If the sig figs are considered then the answer needs to be round to two sig figs and hence the volume becomes 280 mL.
Answer:
46.839728 grams of water
Explanation:
1 mole is equal to 1 moles H2O, or 18.01528 grams
18.01528 times 2.6 = 46.839728
There are 46.839728 grams h20 in 2.60 mol of the compound
Explanation:
hope this helps you..........
Answer: -
6.26 grams
Explanation: -
Atomic Mass of sodium Na = 23 gram
Mass of Na = 18 g
Atomic mass of oxygen O = 16 gram
Molar mass of O2 = 16 x 2 = 32 gram
The balanced chemical equation for the reaction is
4 Na + O2 -- > 2 Na 2 O
From the balanced chemical equation, we see
4 Na requires 1 O2
4 x 23 gram of Na requires 32 gram of O2
18 g of Na gives

= 6.26 grams of O2
For the reaction of formation of Na2O, for 18.0 g of Na, 6.26 grams of O2 are needed for reaction.