Answer is: <span>concentration of fluoride in the water in parts-per-million is 1 ppm.
</span>Parts-per-million (10⁻⁶) is<span> present at one-millionth of a </span>gram per gram of sample solution, f<span>or example mg/kg.
</span>m(fluoride) = 500 g · 1000 mg/g = 500000 mg.
m(water) = d(water) · V(water).
m(water) = 1 kg/L · 500000 L.
m(water) = 500000 kg.
arts-per-million = 500000 mg ÷ 500000 kg = 1 mg/kg = 1 ppm.
According to law of conservation of mass.
In a chemical reaction Mass is neither created nor destroyed.
- Mass of product =Mass of reactant
#1
Mass of water

#2
Mass of sulphur:-

I'm not sure what the question is, this is a lab proecdure
Answer:
can oxygen exist as a liquid and solid
Answer: a) anode
b) positive
c) cathode
d) anode to cathode
Explanation:
Galvanic cell is defined as a device which is used for the conversion of the chemical energy produces in a redox reaction into the electrical energy.
In the galvanic cell, the oxidation occurs at an anode which is a negative electrode and the reduction occurs at the cathode which is a positive electrode. Thus the electrons are produced at anode and travel towards cathode.
Due to loss of electrons at anode, positive charge in concentrated in anode and negative charge is concentrated in cathode. To balance these charges , positive ions or cations from salt bridge move towards cathode and negative ions or anions from salt bridge move towards anode.
The balanced two-half reactions will be:
Oxidation half reaction :
Reduction half reaction :
Thus the overall reaction will be,
