Answer:
The number of protons in an atom is different than the atom’s total mass.
Explanation:
Mendeleev knew only that, with some anomalies, the properties of elements varied periodically with their atomic masses.
Moseley's X-ray experiments enabled him to remove these anomalies and to show that the properties of elements varied with their atomic numbers.
Chadwick later discovered that the mass differences were caused by the presence of neutrons.
Answer:
The possible solution is to balance the rate of water removal from the well to the rate of natural recharge of the well from its underground aquifer.
Explanation:
A well is an excavation in the earth, made with the aim of extracting water from the aquifers. The water from a well can be drawn up by the means of a pump, containers, such as buckets, or by hand. Aquifers can also be recharged through a well.
Well draw down occurs when water from the well is drained faster than it is naturally recharged from the aquifer. This can be as a result of over pumping, extended drought, among other factors. The use of the high-powered motor in this case, for pumping, might be the possible cause of the well drying up. The situation might have resulted from the pump drawing out water from the well at a rate tat exceeds the rate at which it is recharged naturally, causing the well water to start drying up. There's also a possibility that the well is pumped indiscriminately, possibly leading to wastage of water.
The solution to this problem is to give the well a time duration for it to recharge itself. Then, the rate of recharges should be calculated and determined by an hydrologist. When all these is done, a pump with a motor power that does not exceed the calculated recharge rate should be used in place of the high-powered motor. Also, water usage should be brought to the minimum level to prevent unnecessary pumping due to excessive, wasteful use of water.
The balanced reaction is:
4Fe + 3O2 --> 2Fe2O3
Stoichiometrically:
(1.0 mol Fe)(2 mol Fe2O3 / 4 mol Fe) = 0.50 mol Fe2O3
If the actual yield is only 0.325 mol Fe2O3, the % yield can be calculated by dividing actual by theoretical yield:
0.325 / 0.5 x 100% = 65% yield
Answer:
It is called Potassium Hydroxide
