Answer:
0.0984mol of F2
Explanation:
The equation for the reaction is given below:
Kr + F2 → KrF2
Let us convert 12g of KrF2 to mole. This is illustrated below
Molar Mass of KrF2 = 84 + (2x19) = 84 + 38 = 122g/mol
Mass of KrF2 = 12g
Number of mole = Mass /Molar Mass
Number of mole of KrF2 = 12/122 = 0.0984mol
From the equation,
1mole of F2 produced 1mole of KrF2.
Therefore 0.0984mol of F2 will produce 0.0984mol of KrF2
Answer: 0.771 g of 
will be produced
Explanation:
To calculate the moles :
The balanced chemical reaction is:
According to stoichiometry :
2 moles of 
produce = 3 moles of
Thus 0.257 moles of will produce=
of
Mass of 
Thus 0.771 g of will be produced
Answer: NO2
Explanation:
N O
Divide each by its 25.93 74.07
mass number 14 16
2 4
Divide both by the 2 2
smaller (i.e. 2) 1 2
Therefore, the empirical formula = NO2
Answer:
Rb > K > Na > Li
Explanation:
Ionization energy increases up the period and up the group.
From the periodic table, we can see that Li is the going to have the highest ionization energy and Rb is going to have the lowest.
Therefore, the correct answer is the first choice
Answer:
Cl⁻, Na⁺, OH⁻
Explanation:
The titration is:
CuCl₂(aq) + 2 NaOH(aq) → Cu(OH)₂(s) + 2 NaCl(aq)
In solution, before the reaction, the ions are Cu²⁺ and Cl⁻. The addition of NaOH (Na⁺ + OH⁻) produce the precipitation of Cu²⁺ forming Cu(OH)₂(s). When you reach the equivalence point, there is no Cu²⁺ because precipitates completely. All OH⁻ ions reacts when are added but when Cu²⁺ is finished, excess OH⁻ ions still in solution helping to detect the equivalence point.
Thus, ions present after the equivalence point are:<em> Cl⁻, Na⁺</em> (Don't react, spectator ions), and <em>OH⁻</em>.
