Answer:
Mass = 18 g
Explanation:
Given data:
Number of molecules of Dicarbon hexahydride = 3.58 × 10²³ molecules
Mass of Dicarbon hexahydride = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
3.58 × 10²³ molecules × 1 mol / 6.022 × 10²³ molecules
0.6 mol
Mass of Dicarbon hexahydride:
Mass = number of moles × molar mass
Mass = 0.6 mol × 30 g/mol
Mass = 18 g
Answer:
-3.7555 M/s is the rate of change of B.
Explanation:
3A + 5B → 4C
Given that rate of the reaction ,R= 0.7511 M/s
Rate of the reaction is defined as change in concentration of any one of the reactant or product with respect to time.
The negative sign indicates the concentration of reactant B is decreasing with progress in time. This mean reactant B is disappearing.
-3.7555 M/s is the rate of change of B.
Answer:
A. 2 sig figs
Explanation:
In the number 0.0034, the zeros are called leading zeros. The only function of leading zeros is to fix the decimal point. Leading zeros are not counted as significant figures.
Answer:
6.05 g
Explanation:
Molarity of a substance , is the number of moles present in a liter of solution .
M = n / V
M = molarity
V = volume of solution in liter ,
n = moles of solute ,
From the question ,
M = 200mM
Since,
1 mM = 10⁻³ M
M = 200 * 10⁻³ M
V = 250 mL
Since,
1 mL = 10⁻³ L
V = 250 * 10⁻³ L
The moles can be calculated , by using the above relation,
M = n / V
Putting the respective values ,
200 * 10⁻³ M = n / 250 * 10⁻³ L
n = 0.05 mol
Moles is denoted by given mass divided by the molecular mass ,
Hence ,
n = w / m
n = moles ,
w = given mass ,
m = molecular mass .
From the question ,
m = 121 g/mol
n = 0.05 mol ( calculated above )
The mass of tri base can be calculated by using the above equation ,
n = w / m
Putting the respective values ,
0.05 mol = w / 121 g/mol
w = 0.05 mol * 121 g/mol
w = 6.05 g
