Water is the only one of these that would work by process of elimination.
Answer : The complete chemical equation is,

Explanation :
As we know that, in a chemical equation the reacting species present on left side and the product formed present on right side and a right arrow inserted between the reactants and product that show a chemical reaction taking place.
In the chemical reaction, the phases of the substances are also included and subscripts and superscripts are also used for the numbers.
For the given chemical reaction, the balanced chemical equation including the phases, is given by:

First, we write the reaction equation:
NiCO₃ + 2HBr → NiBr₂ + H₂CO₃
Now, writing this in ionic form:
NiCO₃ + 2H⁺ + 2Br⁻ → NiBr₂ + 2H⁺ + CO₃⁻²
(NiCO₃ is insoluble so it does not dissociate in to ions very readily)
Overall equation:
NiCO₃ + 2Br⁻ → NiBr₂ + CO₃⁻²
Answer:
f = 5.25 x 10³⁸ s⁻¹
Explanation:
Energy = 348KJ = 348,000 J
Frequency = ?
Energy and frequency are related by the equation below;
E = hf
where h = Planck's constant = (6.626 x 10-34 J · s),
Upon making f subject of formular;
f = E / h
substituting the values, we have;
f = 348,000 / 6.626 x 10-34
f = 52,520 x 10 ³⁴ s⁻¹
f = 5.25 x 10³⁸ s⁻¹
Answer:
0.363g citric acid
Explanation:
Sodium hydroxide (NaOH) reacts with acids, thus:
NaOH + H⁺ → H₂O + Na⁺
The volume of titration is:
18.39mL - 0.73mL = 17.66mL
Moles of this volume in 0.107M NaOH are:
0.01766L × (0.107 mol / L) = 0.00189mol NaOH ≡ mol citric acid<em> -Assuming the only acid in pear juice is citric acid-</em>
As molar mass of citric acid is 192.124g/mol:, Mass of citric acid is:
0.00189mol citric acid × (192.124g / mol) = <em>0.363g citric acid</em>
I hope it helps!