The amount remaining at the end of 5 half-lives is 7.81×10¹³ g
From the question given above, the following data were obtained:
- Half-life (t½) = 5730 years
- Original amount (N₀) = 2.5×10¹⁵ g
- Number of half-lives (n) = 5
- Amount remaining (N) =?
The amount remaining can be obtained as follow:
N = 1/2ⁿ × N₀
N = 1/2⁵ × 2.5×10¹⁵
N = 1/32 × 2.5×10¹⁵
N = 0.03125 × 2.5×10¹⁵
N = 7.81×10¹³ g
Therefore, the amount remaining after 5 half-lives is 7.81×10¹³ g
Learn more about half-life: brainly.com/question/25783920
Answer:
Exercise 1
a) 140 m
b) 100 m
c) 180 m
d) 140 m
Exercise 2
a) 20 yards
b) 30 yards
c) 20 yards
d) 55 yards
Exercise 3
a) 11 Kilometers
b) 7 Kilometers
Explanation:
Exercise 1
Distance from B to C = 140 m
Distance from to D = 100 m
Total distance = 100+40+40 = 180 m
Total displacement i.e. distance between A and D is 140 m
Exercise 2
a) Distance from B to C = 35 -15 = 20 yards
b) Distance from C to D = 5 + 35 = 30 yards
c) Distance from B to D = 5 + 15 = 20 yards
d) Displacement = 5 + 50 = 55 yards
Exercise 3
a) The total distance travelled = 5 + 2 + 4 = 11 Kilometers
b) Displacement = 5-2 + 4 = 7 Kilometers
It is given that the charge on potassium is +1 i.e. Potassium is a cation, K⁺
The charge on selenium is given as -2, i.e. selenium is an anion, Se²⁻
The two ions are shown to combine to form a molecule: KXSeY where X and Y correspond to the proportions in which the two atoms combine.
Since the molecule is neutral, the positive and negative charges need to be balanced. This is possible only if 2 units of K⁺ combines with 1 unit of Se²⁻.
Therefore, the formula would be K₂Se
X = 2 and Y = 1
Answer:
A more reactive halogen displaces a less reactive halogen from a solution of one of its salts.
Chlorine is more reactive than bromine, thus it displaces bromine.
Answer:
precipitate , chemical
Explanation:
a precipitate is is an insoluble solid that forms when two solutions are combined and react chemically. The two clear colorless liquids is a chemical change because a different solid substance is formed
