The number of hours required : 37.2 hours
<h3>Further explanation</h3>
Given
⁴²K (potassium -42)
Required
The number of hours
Solution
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually, radioactive elements have an unstable atomic nucleus.
Based on Table N(attached), the half-life for ⁴²K is 12.4 hours, which means half of a sample of ⁴²K will decay in 12.4 hours
For three half-life periods :
Answer:
Oxygen comes 8th on the periodic table which is the atomic number.
Explanation:
but Oxygen 13 (Isotopes of Oxygen) is when oxygen has 8 protons and electrons, and 5 neutrons (8+5=13)
NH3 +HCl ----> NH4Cl
moles of HCl used = (0.8 x 17.4) /1000= 0.0139 moles
by use of reacting ratio between HCl to NH4Cl which is 1:1 therefore the moles of NH4Cl is also = 0.0139 moles
molar concentration = moles /volume in liters
molar concentration is therefore= (0.0139/5) x1000 = 2.7 M
Quartz is a substance because the material has uniform properties throughout and is held together via chemical bonds.
B. Add 233 g of KCl to a 3.5 L container; then add enough water to dissolve the KCl and fill the container to the 3.5 L mark.
