The chemical reaction in which number of atoms of each element present in the reactant side is equal to the number of atoms of that element in product side, such reactions are said to be a balanced chemical reaction.
The chemical symbol for sodium is
.
The chemical symbol for fluorine gas is
.
The chemical symbol for sodium fluoride is 
The sodium fluoride is prepared from the reaction between sodium metal and fluorine gas can be written as:

The above reaction is not balanced as the number of fluorine atoms are not same on reactant and product side. So, in order to balance the reaction we will multiply
with 2 on reactant side and
with 2 on product side. Thus, the balanced reaction will be:

Thus, the balanced chemical equation is
.
<h2>Total distance divided by total elapsed time gives : Average speed </h2>
Explanation:
Speed
It is the distance traveled by body with respect to time .
Its formula is Speed = distance /time
V=S/T
units : m/sec or Km/hr
Distance
It is total path traveled by body in any direction .
It unit and symbol is : S and unit = m /Km
Average speed
It is the total distance traveled by body with respect to total time taken to travel that given distance .
Average speed = total distance /total time
A.s = T.D/T.T
unit = m/sec or Km/hr
Instantaneous velocity
It is the distance traveled by body at particular instant of time ,in given direction .
Displacement
It is the shortest path traveled by body in given direction .
Answer:
Ur answer is B. I, II, and III
Explanation:
Tectonic plates can interact with each other.
The mass of NaCl needed for the reaction is 91.61 g
We'll begin by calculating the number of mole of F₂ that reacted.
- Gas constant (R) = 0.0821 atm.L/Kmol
PV = nRT
1.5 × 12 = n × 0.0821 × 280
18 = n × 22.988
Divide both side by 22.988
n = 18 / 22.988
n = 0.783 mole
Next, we shall determine the mole of NaCl needed for the reaction.
F₂ + 2NaCl —> Cl₂ + 2NaF
From the balanced equation above,
1 mole of F₂ reacted with 2 moles of NaCl.
Therefore,
0.783 mole F₂ will react with = 0.783 × 2 = 1.566 moles of NaCl.
Finally, we shall determine the mass of 1.566 moles of NaCl.
- Molar mass of NaCl = 23 + 35.5 = 58.5 g/mol
Mass = mole × molar mass
Mass of NaCl = 1.566 × 58.5
Mass of NaCl = 91.61 g
Therefore, the mass of NaCl needed for the reaction is 91.61 g
Learn more about stiochoimetry: brainly.com/question/25830314