Answer: 1.348 ×10^23 atoms
Explanation:
Given that volume = 1.00L
At standard condition, the volume of a gas is 22.4L/mol (at S.T.P)
Volume = mole /volume at STP
1 = mole/22.4
Mole= 22.4mol.
Also
Mole = number of atoms /Avogradro constant
Where avogrado's constant = 6.02×10²³
22.4 = number of atoms/6.02×10²³
Number of atoms = 1.348×10^25atoms
Answer:
Explanation:
CH₃CHOHCOOH ⇄ CH₃CHOHCOO⁻ + H⁺
ionisation constant = 1.36 x 10⁻⁴ .
molecular weight of lactic acid = 90 g
moles of acid used = 20 / 90
= .2222
it is dissolved in one litre so molar concentration of lactic acid formed
C = .2222M
Let n be the fraction of moles ionised
CH₃CHOHCOOH ⇄ CH₃CHOHCOO⁻ + H⁺
C - nC nC nC
By definition of ionisation constant Ka
Ka = nC x nC / C - nC
= n²C ( neglecting n in the denominator )
n² x .2222 = 1.36 x 10⁻⁴
n = 2.47 x 10⁻²
nC = 2.47 x 10⁻² x .2222
= 5.5 x 10⁻³
So concentration of hydrogen or hydronium ion = 5.5 x 10⁻³ g ion per litre .
Answer:
Count how many significant figures are in a number, and find which digits are significant. You can use this calculator for significant figures practice: Test your ability to find how many significant figures are in a number.Enter whole numbers, real numbers, scientific notation or e notation. Example inputs are, 3500, 35.0056, 3.5 x 10^3 and 3.5e3.
Explanation:
Answer:
35.453g/mol is the average atomic mass of the element
Explanation:
The average atomic mass of an element is defined as the sum of the mass of its isotopes multiplied by its natural abundance.
The element of the problem has 2 isotopes:
The first with a mass of 34.969g/mol and its abundance is 75.77%
The second has a mass of 36.966g/mol and its abundance is 24.23%
Its natural abundance is:
34.969g/mol * 75.77% + 36.966g/mol * 24.23%
<h3>35.453g/mol is the average atomic mass of the element</h3>