The answer is (2) KNO3. This depends on the solubility of these four compounds at 10℃. For NaCl, it is 35.8 g, For NaNO3, 80.8 g. KCl, 31.2 g. KNO3, 21.9g. So only KNO3 is less than 25.0 g.
Answer:
223.5 g
Explanation:
The formula between the number of moles, mass and Mr can be used to convert moles to grams.
<em>Number of moles = mass ÷ Mr</em>
So, mass = number of moles × Mr
Mr of Li₂O = (6.9 × 2) + 16 = 29.8
∴ Mass = 7.5 × 29.8 = <u>223.5 g</u>
Answer: Rb gains two electrons
Explanation:
Answer:
Independent: The amount of vinegar
Dependent: The dye result on the egg
Controlled: The type of eggs, the size of jars, the dye tablet, how much she stirs, etc.
Explanation:
The independent variable is what is being changed, which in this case, is the amount of vinegar being added to each jar. The dependent variable is what is being measured or observed. Kesha is looking for what happens to the egg when she adds more vinegar with the dye. Lastly, there could be a couple of controlled variables. Like, the dye tablet, the size and brand of the eggs, the types of jars, how long she stirs each egg, and so on. The controlled are just variables kept constant so that any result observed is because of one singular change, the independent variable.
You are given a galvanic cell consists of a Ni²⁺/ Ni half-cell and a standard hydrogen electrode. Also, you are given that the half cell Ni²⁺/ Ni will act as an anode, and the standard cell potential is 0.26V. You are asked to find the standard reduction potential for the half cell Ni²⁺/ Ni.
You will have a half - reaction for both nickel and hydrogen
The conversion of the symbol Ni²⁺/ Ni half-cell is
Ni²⁺ + 2e⁻ → Ni (s) E = 0.26V
and the conversion of the standard hydrogen electrode (SHE) is
2H⁺ + 2e⁻ → H₂ (g) E = 0V
Since H⁺ ions is a it difficult to set up during the process, nickel will be deposited at the cathode side instead of the anode. Therefore, The standard electron potential of the nickel will have -0.26V.
