Answer:
39.02 amu
Explanation:
The average atomic mass of an element can be calculated as follows :
So, the atomic mass of the element X is 39.02 amu.
Answer:
C. 64
Explanation:
Given:
The number of equally likely sample outcomes of a single stage = 4
Unknown:
Total number of elements if there are three stages= ?
Solution;
Probability is the likelihood of an event to occur.
In this problem;
For a single stage, the likely outcome is 4
So therefore;
For the 3 stages 4 x 4 x 4 = 64
Therefore, the total number of elements in the sample space of an experiment with 3 stages is 64
There is two of these questions
Q1)
molarity is defined as the number of moles of solute in 1 L of solution.
the NaCl solution volume is 1.00 L
number of moles NaCl = NaCl mass present / molar mass of NaCl
NaCl moles = 112 g / 58.5 g/mol = 1.91 mol
the number of moles of NaCl in 1.00 L of solution is - 1.91 mol
therefore molarity of NaCl is 1.91 M
Q2)
molality is defined as the number of moles of solute in 1 kg of solvent.
density is mass per volume.
density of the solution is 1.08 g/mL.
therefore mass of the solution is = density x volume
mass = 1.08 g/mL x 1000 mL = 1080 g
since we have to find the moles in 1 kg of solvent
mass of solvent = 1080 g - 112 g = 968 g
number of moles of NaCl in 968 g of solvent - 1.91 mol
therefore number of NaCl moles in 1000 g - (1.91 mol / 968 g) x 1000 g/kg = 1.97 mol/kg
molality of NaCl solution is 1.97 mol/kg
Q3)
mass percentage is the percentage of mass of solute by total mass of the solution
mass percentage of solution = mass of solute / total mass of the solution
mass of solute = 112 g
total mass of solution = 1080 g
mass % of NaCl = 112 g / 1080 g x 100%
therefore mass % of NaCl = 10.4 %
answer is 10.4 %
Explanation:
2.04 % hydrogen
32.65% sulphur
65.31% is oxygen
atomic ratio
hydrogen =2.04÷1=2.04
sulphur =32.65÷32=1.02
oxygen =65.31÷16=4.08
simplest ratio
hydrogen = 2.04÷1.02=2
sulphur =1.02÷1.02=1
oxygen =4.08÷1.02=4
empirical formula is H2SO4
