The daughter isotope : Radon-222 (Rn-222).
<h3>Further explanation</h3>
Given
Radium (Ra-226) undergoes an alpha decay
Required
The daughter nuclide
Solution
Radioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles,
- alpha α particles ₂He⁴
- beta β ₋₁e⁰ particles
- gamma particles ₀γ⁰
- positron particles ₁e⁰
- neutron ₀n¹
The decay reaction uses the principle: the sum of the atomic number and mass number before and after decay are the same
Radium (Ra-226) : ₈₈²²⁶Ra
Alpha particles : ₂⁴He
So Radon-226 emits alpha α particles ₂He⁴ , so the atomic number decreases by 2, mass number decreases by 4
The reaction :
₈₈²²⁶Ra ⇒ ₂⁴He + ₈₆²²²Rn
Answer:
A feasible error could have been the removal of the sample before all water evaporated.
Explanation:
In order to determine the percentage of water in an hydrate, an experiment that could be performed is the heating of the sample until the mass does not change. If the student heated the sample an insufficient amount of time, water will be present in the sample, thus reducing the percentage reported.
Correct question
The density of liquid mercury is 13.6 g/mL. What is its density in units of lb/in3? (2.5 cm = 1 in., 2.205 lbs= 1 kg., 1000 g =1 kg, 1 mL = 1 cm³)
Answer:

Explanation:
Given that;-
The density = 13.6 g/mL
Also, 1 kg = 2.205 lb
1 kg = 1000 g
So, 1000 g = 2.205 lb
1 g = 0.002205 lb
Also,
1 in = 2.54 cm
1 in³ = 16.39 cm³
1 cm³ = 1 mL
So, 1 in³ = 16.39 mL
1 mL = 0.061 in³
The expression for the calculation of density is shown below as:-

Thus,

P1V1=P2V2
(1.00atm)(3.60L)=(2.50atm)V
3.60=(2.50atm)V
3.60/2.50=V
1.44L=V