<span>SulphurS 161s22s22p63s23p<span>4</span></span>
The answer is B Ni(s)
nickel atom will oxidised to become nickel ion, Ni2+
1) <span> 2.7 g water + 6,6 g carbon dioxide </span>→<span> 9.3 g carbonic acid.
According to </span><span>principle of mass conservation mass of reactants and products are the same after chemical reactio. 2,7 g + 6,6 g = 9,3 g.
2) </span><span>32.0 g sodium hydroxide + 16.0 g hydrofluoric acid --> 14,4 g water + 33.6 g sodium fluoride.
m(water) = 32 g + 16 g - 33,6 g.
3) </span><span>0.60 g calcium carbonate + 0.48 g sodium hydroxide --> 0,63 g sodium carbonate + 0.45 g calcium.
m(sodium carbonate) = 0,6 g + 0,48 g - 0,45 g.
4) </span><span>0.53 g sodium hydroxide + 0.37 g carbon dioxide --> 0,9 g sodium hydrogen carbonate.
m(sodium hydrogen carbonate) = 0,53 g + 0,37 g = 0,9 g.</span>
Answer:
V1= 0.305L
Explanation:
To find the initial volume of 1.25M potassium fluoride needed to make tge dilution specified in the question, we can use: C1 × V1 = C2 × V2
Since the question wants the volume in litres, convert 455 mL to L
455/ 1000
= 0.455 L
Now make the substitution
1.25 × V1 = 0.838 × 0.455
Rearrange to make V1 the subject
V1=

Answer:
the answer should be six months