I believe it’s the third option
Chemically combined to make a new pure substance
Answer:
67.492cm^3
Explanation:
To get the volume of tetrahydrofuran needed, what the student need to do is to apply mathematical calculations.
We know quite well that to obtain the volume of a substance, given the mass of the substance and the density of the substance is possible.
The volume of the substance is simply the mass of the substance divided by the density of the substance.
This is thus volume = mass/density
The mass given is the question is 60g while the density given is 0.889g/cm^3
The volume = 60/0.889 = 67.492cm^3
Answer:
0.72 g of the lower oxide gave 0.8 g of higher oxide when oxidised. ... Thus, 90g of lower oxide contains as much metal as 100g of higher oxide, i.e., 80g (given). Hence, 80g of metal combines with 10g of oxygen in the lower oxide and 20g of oxygen in the higher oxide.
Group 1 and group 7 of element group consists of alkali metal, which are generally combined with other elements in nature, so they have properties of compound
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
