While staying in the same period, if we move from left to right across the period, the atomic radius decreases. The reason is, in a period the number of shells remain the same and the number of electrons and protons increase as we move across the period to the right. The increased electrons and protons attract each other with greater force and hence the atomic size decreases.
So the element on the left most will have the largest atomic radius. So the correct ans is Potassium. Potassium will have the largest atomic size among Potassium, Calcium and Scandium.
30% should be the percentage of oxygen if the total mass of fe2o3 is 160.
Based on the given conditions, the gravitational force acted on the body is greater than the force upward by a quantity equal to 500 N. Therefore, the net force will cancel out and will remain an amount of 500N downward relative to the gravitational force exerted by the object.
The balanced chemical reaction is:
<span>2H2O= 2H2 + O2
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We are given the amount of oxygen to be produced in the reaction. The starting point for the calculations will be this amount.
50 g ( 1 mol O2 / 32 g O2 ) ( 2 mol H2O / 1 mol O2 ) ( 18.01 g H2O / 1 mol H2O) = 56.28 g of H2O is needed.
Therefore, the correct answer is the last option.
<span>Use the sequence E (NaCl, Na2SO4, then Na2S). Silver is insoluble as a chloride, so it would be removed first, the others (Pb and Ni) are soluble as chlorides(Note; lead chloride is soluble as a hot solution but will ppt when cold), next, PbSO4 is insoluble but NiSO4 is soluble so use Na2SO4 to separate lead from nickel. Lastly, nickel sulfide is insoluble and can be separated and collected.
Hope I helped :)</span>
