To solve this, we can use two equations.
t1/2 = ln 2 / λ = 0.693 / λ
where, t1/2 is half-life and λ is the decay constant.
t1/2 = 10 min = 0.693 / λ
Hence, λ = 0.693 / 10 min - (1)
Nt = Nο e∧(-λt)
Nt = amount of atoms at t =t time
Nο= initial amount of atoms
t = time taken
by rearranging the equation,
Nt/Nο = e∧(-λt) - (2)
From (1) and (2),
Nt/Nο = e∧(-(0.693 / 10 min) x 20 min)
Nt/Nο = 0.2500
Percentage of remaining nuclei = (nuclei at t time / initial nuclei) x 100%
= (Nt/Nο ) x 100%
= 0.2500 x 100%
= 25.00%
Hence, Percentage of remaining nuclei is 25.00%
Answer:
6.1 cm³
Explanation:
To solve this problem we first need to keep in mind <em>Archimedes' principle</em>:
- The volume of water (or any fluid) displaced by a submerged object is equal to the object's volume.
With that in mind we <u>calculate the volume of the granite piece in mililiters</u>:
- Volume displaced = 47.6 mL - 41.5 mL = 6.1 mL
- Volume of the granite piece = 6.1 mL
Given that one cubic centimeter is equal to one mililiter, the volume of the granite piece in cm³ is 6.1 cm³.
Answer:
0.147 mol
Explanation:
Step 1: Calculate the volumetric concentration (Cv)
We will use the following expression.
Cv = Cg × ρ
Cv = 98.0 g%g × 1.84 g/mL = 180 g%mL
Step 2: Calculate the molarity of sulfuric acid
We will use the following expression.
M = mass solute / molar mass solute × liters of solution
M = 180 g / 98.08 g/mol × 0.100 L = 18.4 M
Step 3: Calculate the moles of solute in 8.00 mL of solution
8.00 × 10⁻³ L × 18.4 mol/L = 0.147 mol
Roman numerals are used in naming ionic compounds when the metal cation forms more than one ion. The metals that form more than one ion are the transition metals, although not all of them do this.
