or simply 2,8 it is isoelectronic with argon
Answer:
12.50g
Explanation:
T½ = 2.5years
No = 100g
N = ?
Time (T) = 7.5 years
To solve this question, we'll have to find the disintegration constant λ first
T½ = In2 / λ
T½ = 0.693 / λ
λ = 0.693 / 2.5
λ = 0.2772
In(N/No) = -λt
N = No* e^-λt
N = 100 * e^-(0.2772*7.5)
N = 100*e^-2.079
N = 100 * 0.125
N = 12.50g
The sample remaining after 7.5 years is 12.50g
.A solution that serves as a pH indicator may be made using red cabbage, which is frequently available in homes. In essence, the color of the cabbage depends on the acidity of the solution and a pigment molecule called flavin or anthocyanin.
To determine whether a material is an acid or a base, red cabbage indicator is a purple-colored solution
Vinegar is an acid and its pH value is less than 7 and hence
Red color is produced
Baking soda is base and its pH value is greater than 7 and between 8-9
and the color produced is sky blue
Bleach is the green which is also a basic and because the pH value is 10-11
Householder cleaner is having pH 11-13 which is basic and hence the yellow is the color of household cleaner .
A basic solution goes away from being basic and toward the center of the pH scale when an acid is introduced. The base is "neutralized" in this manner.
Learn more about pH value here
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Answer: $46.98
Explanation:
The distance to drive to Los Angeles from San Francisco is 405 miles. Since the car get 25 miles per gallon of gas, for 405 miles, the car will use:
= 405/25 = 16.2 gallons
Since the cost of gasoline is $2.90 a gallon and the car will use 16.2 gallons. The cost will be:
= $2.90 × 16.2 gallons
= $46.98
Conduction - by touch
Convection - hot air rises, cold air sinks
Insulation - to insulate or capture heat
Radiation - by waves
Direct contact means touch, therefore the answer would be conduction.
