Answer:
See explanation
Explanation:
The valence electrons are electrons found on the valence (outermost) shell of an atom.
When an atoms form compounds, there is an exchange of valence electrons between the atoms of one element and the atoms of another element.
Let us consider a typical example, sodium has one valence electron and chlorine has seven valence electrons. This means that chlorine needs one electron to complete its octet while sodium needs to release one electron in order to attain the octet structure.
So, sodium gives out its one electron and becomes a stable sodium ion and chlorine accepts that electron and becomes a stable chloride ion. This is how the compound sodium chloride is formed.
Answer:
6.791
Explanation:
For proper significant figures with addition, you would use the significant figures of the number with lowest decimal place. 6.298 goes to the 10⁻³ place. 0.492712 goes to the 10⁻⁶ place. You will go out to the 10⁻³ place.
6.298 + 0.492712 = 6.790712 ≈ 6.791
The car will travel 387 ft in 5.00 s.
No. of kilometres = 5.00 s × (1 min/60 s) × (1 h/60 min) × (85.0 km/h) = 0.1181 km
No of feet = 0.1181 km × (1 mi/1.609 km) × (5280 ft/1 mi) = 387 ft
Answer:
0.01 faraday
Explanation:
We'll begin by writing the balanced equation. This is illustrated below:
CaCl₂ (aq) —> Ca²⁺ (aq) + 2Cl¯ (aq)
Ca²⁺ (aq) + 2e —> Ca
Molar mass of Ca = 40 g/mol
Mass of Ca from the balanced equation = 1 × 40 = 40 g
1 mole of electron (e) = 1 faraday
2 moles of electrons (e) = 2 × 1 faraday
2 moles of electrons (e) = 2 faraday
From the balanced equation above,
40 g of Ca was deposited by 2 faraday.
Therefore, 0.2 g of Ca will be deposited by = (0.2 × 2)/40 = 0.01 faraday.
Thus, 0.01 faraday is needed for the reaction.
