We have to get the stable atom formed after positron emission from Terbium-147.
The stable atom is (D) ₆₄Gd¹⁴⁷.
Positron is radioactive decay. Positron is a type of beta particle β⁺.
Positron emission decreases proton number relative to neutron number, positron decay results in nuclear transmutation, changing an atom of one chemical element with an atomic number that is less by one.
Terbium on positron emission produces Gadolinium with one atomic number less than Terbium. So, the positron emission reaction is as shown below:
Tb¹⁴⁷→ ₆₄Gd¹⁴⁷ + ₁e⁰
Answer:
−2399.33 kJ
Explanation:
If NH₄NO₃ reacts with fuel oil to give a ΔH of -7198 for every 3 moles of NH₄NO₃
What is the enthalpy change for 1.0 mole of NH₄NO₃ in this reaction
∴ For every 1 mole, we will have 
of the total enthaply of the 3 moles
so, to determine the 1 mole; we have:
= −2399.33 kJ
∴ the enthalpy change for 1.0 mole of NH₄NO₃ in this reaction = −2399.33 kJ
1 mole ----------- 22.4 L ( at STP )
3.75 moles ----- ?
3.75 x 22.4 / 1 => 84.0 L
The element iodine (I) is important for the fast and hastened metamorphosis of frog-tadpoles. As amphibians, the tadpoles can live in water and land but when they are born they are iodine-deficient. Tadpoles that do not receive ample amount of iodine become tadpoles until the end of their days.
To calculate the mass of milk of magnesia given, we need certain data like molar mass of the compound which needs the atomic mass of the atoms in the compound. We calculate as follows:
Molar mass of <span>Mg(OH)2 = 24.3 g/mol + (2 x (16 + 1.0)) = 58.30 g/mol
Mass = 3.2 mol (</span>58.30 g/mol) = 186.56 grams
