Answer:
The answer to your question is 5.74 g of Silver
Explanation:
Data
number of atoms = 3.20 x 10²²
mass of silver = ?
Process
The atomic number of an element is equal to Avogadro's number (6.023 x 10²³).
1.- Look for the atomic number of Silver
Atomic number = 108 g
2.- Use proportions to calculate the grams of silver
108 g of Silver ----------------- 6.023 x 10²³ atoms
x ------------------ 3.20 x 10²² atoms
x = (3.20 x 10²² x 108) / 6.023 x 10²³
x = 3.456 x 10²⁴/ 6.023 x 10²³
x = 5.74 g of Silver
The correct answer is option B. The amphibian and mosses belonged to the same age.
Since the rocks belong to the same age and one contain fossils of an amphibian and the other containing fossils of mosses, it is very likely that both the amphibian and the mosses existed at the same time.
Sedimentary rocks generally have fossils in them and it is very easy to determine the age of the fossils from Radiometric Dating using radioactive carbon C¹⁴. However, before the complete understanding of radioactive decay fossil, age was determined by studying the succession of fossils on old to younger sedimentary rocks.
Answer:
The standard reaction free energy = -144 kj
Explanation:
According to Electrochemical series
Standard reduction potential of
- Cl₂ + 2 e⁻ → 2 Cl⁻ E⁰ = +1.36 volt .................(i)
- MnO₄⁻ + 8H⁺ + 5 e⁻ → Mn²⁺ + 4 H₂O E⁰ = +1.51 volt ..................(ii)
Since Permanganate have more positive reduction potential so it is used as a cathode half cell and chlorine as a anode half cell
Cathode half cell (Reduction) MnO₄⁻ + 8H⁺ + 5 e⁻ → Mn²⁺ + 4 H₂O ...(3)
Anode half cell (Oxidation) 2 Cl⁻ → Cl₂ + 2 e⁻ ...............................(4)
Multiplication by 2 of equation (3) and by 5 of equation(4)
10Cl⁻(aq) + 2MnO₄⁻(aq) + 16H⁺(aq) = 5Cl₂(g) + 2Mn²⁺(aq) + 8H₂O(l)
E.M.F of the combined cell reaction
E⁰ = E⁰cathode - E⁰anode = 1.51 - 1.36 = 0.15 v
⇒ ΔG⁰ reaction = - nF E⁰cell
n = no, of electron exchange = 10
⇒ΔG⁰ reaction = - 10 x 96500 x 0.15
= - 144750 j
= - 144 kj (round off by 3 significant fig.)
Answer:
The new concentration will be 0.01 M.
Explanation:
To determine the new concentration we use the following formula.
concentration (1) × volume (1) = concentration (2) × volume (2)
concentration (1) = 0.1 M
volume (1) = 100 mL
concentration (2) = unknown
volume (2) = 100 mL + 900 mL = 1000 mL
concentration (2) = [concentration (1) × volume (1)] / volume (2)
concentration (2) = (0.1 × 100) / 1000 = 0.01 M
Density=mass / volume
23.4 =mass/ 75
75x23.4= 1755 g = mass