Alkali: Group 1(I A). Halogens: group 17 (VII A)
Answer:
The two elements with atomic number 9 and 12 are represented by letter Q and R respectively, where Q represents fluorine atom and R represents magnesium atom.
1. Electronic configuration of R that is magnesium (atomic number 12) is:
1s2 2s2 2p6 3s2
2. Q represents fluorine atom, which belongs to group 17 in periodic table that is the most reactive and lightest member of the group.
3. Q and R that is fluorine and magnesium combinely form magnesium fluoride or MgF2.
Answer:
There is 26.58 grams of gold formed
Explanation:
Step 1: Data given
17.6 A of current are passed through a gold solution for 37.0 min
Molar mass of Au = 196.967 g/mol
Step 2: The equation
Au^3+ + 3e- → Au
Step 3: Calculate coulombs
17.6 Coulomb/s * 37.0 min * 60 sec/min = 39072 Coulombs
1 Faraday = 96500 Coulombs
Step 4: Calculate faraday
39072 Coulombs / 96500 Coulombs / Faraday = 0.40489 Faraday
Step 5: Calculate mass of gold formed
For every 3 Faraday of electricity used up , 1 mole Au is formed
0.40489 Faraday * 1 mole Au/ 3 Faraday = 0.13496 mole Au
196.967 g/mol * 0.13496 mol = 26.58 g Au
There is 26.58 grams of gold formed
Katniss
Is
Never
Ever
That
Incredibly
Cumbersome
(Peeta on the other hand was cumbersome to Katniss's hunting in the Games.)
The most common solvent is- Water. Water can dissolve in various different substances, and it dissolves more substances than any other liquid. In fact, some people call it the<em>"universal solvent".</em>