<span>Nickel
is an element with a mass number of 58.6934 u <u>+</u> 0.0002 u.
It has a symbol of Ni and an atomic number of 28. Nickels are usually used to
make US coins because it is a silvery-while metal. It was Axel Fredrik
Cronstedt who were said to discover Nickel in year 1751. The melting point is
Nickel is 2 651 degree F or equals to 1 455 degree C. It is also said to be
hard and ductile.</span><span>
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It's going to be the first one which is "A" for true
Answer:
1. The salt bridge completes the circuit of the voltaic cell to allow the flow of current
2. The porous divider performs the function of a salt bridge, hence a salt bridge is unnecessary in a single-beaker voltaic cell
Explanation:
1. The oxidation and reduction half cells of a voltaic cell are connected by the salt bridge in other to ensure that the internal circuit is electrically neutral, to avoid the rapid reaction to reach equilibrium conditions which affects results in preventing voltage drop in the voltaic cell.
The salt bridge also aids in charge accumulation
2. In a single-beaker voltaic cell with the compartments separated by a porous divider, the function of the porous divider is the same as that of the salt bridge, hence the salt bridge is unnecessary.
Answer:
174.8 g/m is the molar mass of the solute
Explanation:
We must apply colligative property of freezing point depression.
ΔT = Kf . m . i
ΔT = T° freezing pure solvent - T° freezing solution (0° - (-2.34°C) = 2.34°C
Kf = Fussion constant for water, 1.86 °C/m
As ascorbic acid is an organic compound, we assume that is non electrolytic, so i = 1
2.34°C = 1.86°C/m . m
2.34°C / 1.86 m/°C = 1.26 m
This value means the moles of vitamin C, in 1000 g of solvent
We weighed the solute in 250 g of solvent, so let's calculate the moles of vitamin C.
1000 g ___ 1.26 moles
In 250 g ___ (250 . 1.26)/1000 = 0.314 moles
This are the moles of 55 g of ascorbic acid, so the molar mass, will be:
grams / mol ⇒ 55 g/0.314 m = 174.8 g/m
Carbon is produced by producers, consumed by consumers, released by consumers, and returned to the air and soil by decomposers.