Answer:
Generally, the first ionisation energy increases along a period. But there are some exceptions one which is not an exception
Sulfur trioxide (SO3) is a chemical compound that is a significant pollutant in gaseous form as it is involved in the production of acid rain.
Industrially, sulfur trioxide is an important precursor to sulfuric acid and is formed from the reaction between sulfur dioxide (SO2) and oxygen gas (O2) as shown in the chemical equation below.
Answer:
a) 
b) 
c) 
Explanation:
The symbols of the isotopes are written like

where,
X is the element
A is the mass number (protons + neutrons)
Z is the atomic number (protons)
<em>a) Iodine-131</em>
The atomic number of iodine is 53. The mass number of this isotope is 131. The symbol is
.
<em>b) Iridium-192</em>
The atomic number of iridium is 77. The mass number of this isotope is 192. The symbol is
.
<em>c) Samarium-153</em>
The atomic number of samarium is 62. The mass number of this isotope is 153. The symbol is
.
Yes, the atomic radius increases as you move down a group of elements.
this is true
going down leads to valence electrons that are further away from nucleus -> less electrostatic attraction -> less pull towards nuc. -> greater radius/volume taken
Answer:
pH ≅ 4.80
Explanation:
Given that:
the volume of HN₃ = 25 mL = 0.025 L
Molarity of HN₃ = 0.150 M
number of moles of HN₃ = 0.025 × 0.150
number of moles of HN₃ = 0.00375 mol
Molarity of NaOH = 0.150 M
the volume of NaOH = 13.3 mL = 0.0133
number of moles of NaOH = 0.0133× 0.150
number of moles of NaOH = 0.001995 mol
The chemical equation for the reaction of this process can be written as:

1 mole of hydrazoic acid react with 1 mole of hydroxide to give nitride ion and water
thus the new number of moles of HN₃ = 0.00375 - 0.001995 = 0.001755 mol
Total volume used in the reaction = 0.025 + 0.0133 = 0.0383 L
Concentration of
=
= 0.0458 M
Concentration of
=
= 0.0521 M
GIven that :
Ka = 
Thus; it's pKa = 4.72




pH ≅ 4.80