The answer is D because, hope this helps
2.1618 grams of P4 is required to produce 4.21x10^22 molecules of phosphorus trifluoride.
Explanation:
The balanced chemical reaction for formation of PF3 from yellow phosphorus is given by:
P4 + 6F2 ⇒ 4PF3
1 mole of P4 reacts to give 4 moles of PF3
It is given that 4.21x10^22 molecules of PF3 are produced
so the number of moles can be calculated by the relation
number of molecules = number of moles × Avagadro number
number of moles = 
n = 
n= 0.06989 moles of PF3 is formed.
Applying stoichiometry,
1 mole of P4 gives 4 moles PF3
x mole will produce 0.06989 moles of PF3
= 
4x= 0.0698 × 1
x = 
x= 0.01745 moles of P4 will be required.
The weight of the phosphorus can be obtained by number of moles × atomic mass of one mole of P4
= 0.01745 × 123.89
= 2.1618 grams of P4.
Answer: B represents an element.
Answer:
Explanation:
Chemical equation:
FeCl₃ + NaOH → Fe(OH)₃ + NaCl
Balanced chemical equation:
FeCl₃ + 3NaOH → Fe(OH)₃ + 3NaCl
Step 1:
FeCl₃ + NaOH → Fe(OH)₃ + NaCl
Fe = 1 Fe = 1
Cl = 3 Cl = 1
Na = 1 Na = 1
OH = 1 OH = 3
Step 2:
FeCl₃ + 3NaOH → Fe(OH)₃ + NaCl
Fe = 1 Fe = 1
Cl = 3 Cl = 1
Na = 3 Na = 1
OH = 3 OH = 3
Step 3:
FeCl₃ + 3NaOH → Fe(OH)₃ + 3NaCl
Fe = 1 Fe = 1
Cl = 3 Cl = 3
Na = 3 Na = 3
OH = 3 OH = 3
Now we the equation is completely balanced and follow the law of conservation of mass because there are equal number of atoms of each elements are present on both side.
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction
.
Type of reaction:
It is double displacement reaction.
Double replacement:
It is the reaction in which two compound exchange their ions and form new compounds.
AB + CD → AC +BD
The reactants has 2 NO2 and the product has 3. So we need to make sure we have 6 on each side.
Al + 3Fe(NO2)2 -> Fe + 2Al(NO2)3
This leaves us with us just to balance the Fe And Al
2Al + 3Fe(NO2)2 -> 3Fe + 2Al(NO2)3
Hope this helped :)
