Answer:
Determine the location of the lost significant place value by placing a bar over the digit.
Explanation:
64 divided by 4 is 16, so 16 km every 15 minutes.
15 x 3 is 45, so the distance is 16 x 3, and 16 x 3 equals 48.
It has traveled 48 km after traveling for 45 minutes. Hope this helped :)
We are told that there are 1.55 x 10²³ molecules of Cl₂ and we need to calculate the mass of these molecules. We need to do several conversions. The easiest will be to convert the amount of molecules to the number of moles present. To do this, we need to use Avogadro's number which is 6.022 x 10²³ molecules/mole.
1.55 x 10²³ molecules / 6.022 x 10²³ molecules/mole = 0.257 moles Cl₂
Now that we have the moles of Cl₂ present, we can convert this value to a mass of Cl₂ by using the molecular mass of Cl₂. The molecular mass is 70.906 g/mol.
0.257 moles Cl₂ x 70.906 g/mol = 18.3 g Cl₂
Therefore, 1.55 x 10²³ molecules of Cl₂ will have a mass of 18.3 g.
Sublimation is when a solid turns directly into a gas, completely bypassing the liquid phase. Dry ice is a good example.