Answer 1) It is incorrect.
Explanation : For the statement;
Thomson did experiments with cathode ray tubes to show that all atoms contain tiny negatively charged subatomic particles called as electrons<span>.
So the statement should be like this:
AFTER the </span><span>Thomson’s experiments, scientists accepted that the atom was made up of smaller particles.
Answer 2) This is correct.
Explanation : Rutherford was the scientist who discovered that atoms has volume is because of the empty spaces inside it. He did the gold foil experiments to prove this and he was successful in doing this by concluding that tiny dense empty places are occupied by positively charged nucleus.
Answer 3) This is Correct.
Explanation : After Thomson and Rutherford, Millikan also performed an experiment to prove that an atom contains a small positively charged nucleus which is usually surrounded by negatively charged electrons by his oil drop experiment.</span>
Answer:
2.29 × 10²⁴ atoms Na
Explanation:
Step 1: Define
Avagadro's Number: 6.02 × 10²³ atoms, molecules, formula units, etc.
Step 2: Stoichiometry
= 2.2876 × 10²⁴ atoms Na
Step 3: Simplify
We have 3 sig figs.
2.2876 × 10²⁴ atoms Na ≈ 2.29 × 10²⁴ atoms Na
He Rydberg formula can be extended for use with any hydrogen-like chemical elements.
<span>1/ λ = R*Z^2 [ 1/n1^2 - 1/n2^2] </span>
<span>where </span>
<span>λ is the wavelength of the light emitted in vacuum; </span>
<span>R is the Rydberg constant for this element; R 1.09737x 10^7 m-1 </span>
<span>Z is the atomic number, for He, Z =2; </span>
<span>n1 and n2 are integers such that n1 < n2 </span>
<span>The energy of a He+ 1s orbital is the opposite to the energy needed to ionize the electron that is </span>
<span>taking it from n = 1 (1/n1^2 =1) to n2 = ∞ (1/n2^2 = 0) </span>
<span>.: 1/ λ = R*Z^2 = 1.09737x 10^7*(2)^2 </span>
<span>λ = 2.278*10^-8 m </span>
<span>E = h*c/λ </span>
<span>Planck constant h = 6.626x10^-34 J s </span>
<span>c = speed of light = 2.998 x 10^8 m s-1 </span>
<span>E = (6.626x10^-34*2.998 x 10^8)/(2.278*10^-8) = 8.72*10^-18 J ion-1 </span>
<span>Can convert this value to kJ mol-1: </span>
<span>(8.72*10^-18*6.022 x 10^23)/1*10^3 = 5251 kJ mol-1 </span>
<span>Lit value: RP’s secret book: 5240.4 kJ mol-1 (difference is due to a small change in R going from H to He+) </span>
<span>So energy of the 1s e- in He+ = -5251 kJ mol-1</span>
The engine ran for 10 second
ANSWER - 48.83%
Mg - 24.31
S - 32.07
O - 16x4 - 64
ADD ALL TOGETHER = 120.38
H - 1.01x2 - 2.02
O - 16
TOTAL = 18.02x7 = 126.14
ADD 120.38 to 126.14 = 246.52
last part divide MgSO4 by total compound mass
120.38/246.52 then multiply by 100 = 48.831
