Answer:
Explanation: A chemical change is a reaction in which chemical composition of the substance changes. Some bonds are broken and some new bonds are formed.
The reactants are written in terms of their chemical formula on the left hand side and the products are written in terms of their chemical formula on right hand side with a arrow in between. The chemical symbols are followed by their physical states such as (l) for liquid, (s) for solid, (g) for gas and (aq) for aqueous.
Thus the only reaction producing a gas is 
Answer:
<h3>Therefore, after long period of time 80kg of salt will remain in tank</h3>
Explanation:
given amount of salt at time t is A(t)
initial amount of salt =300 gm =0.3kg
=>A(0)=0.3
rate of salt inflow =5*0.4= 2 kg/min
rate of salt out flow =5*A/(200)=A/40
rate of change of salt at time t , dA/dt= rate of salt inflow- ratew of salt outflow

integrating factor

integrating factor 
multiply on both sides by 

integrate on both sides
b)
after long period of time means t - > ∞

<h3>Therefore, after long period of time 80kg of salt will remain in tank</h3>
Answer:
V = 3.1 L
Explanation:
Given data:
Molarity of solution = 0.37 M
Mass of LiF = 29.53 g
Volume of solution = ?
Solution:
Number of moles of LiF:
Number of moles = mass/molar mass
Number of moles = 29.53 g/ 25.94g/mol
Number of moles = 1.14 mol
Volume:
Molarity = number of moles of solute / Volume in L
0.37 M = 1.14 mol / V
V = 1.14 mol / 0.37 M
V = 3.1 L (M = mol/L)