Consider the following ionic compounds: CdCO3, Na2S, PbSO4, (NH4)3PO4, and Hg2Cl2. Which compounds will be soluble when added to water

Na2S, (NH4)3PO4

Explanation:

We can decide what compounds are soluble by considering the solubility rules that apply.

CdCO3 is not soluble in water because all carbonates are insoluble except those of ammonium, sodium and potassium.

Na2S is soluble in water because all sulphides are insoluble except those of sodium, potassium and ammonium.

PbSO4 is insoluble in water because all sulphates are soluble except those of lead and barium. The sulphate of calcium is only slightly soluble in water.

(NH4)3PO4 is soluble in water because all phosphates are insoluble except those of sodium, potassium and ammonium.

Hg2Cl2 is insoluble in water because all chlorides are soluble except those of lead, mercury II and silver.

it takes on an electronical energy

most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

the political sponsor of weights and measures reform in the french revolutionary national assembly was the bishop of autun, better known as talleyrand. under his auspices, the french academy appointed several committees to carry out the work of developing a usable system of weights and measures for france. one of the committees recommended a decimalized measurement system based upon a length equal to one ten-millionth of the length of a quadrant of the earth’s meridian (i.e., one ten-millionth of the distance between the equator and the north pole).