Mention the occurrence of nitrogen and phosphorus in the earth's crust. 

Uraemia is the occurrence of

Name the chief forms of the occurrence of the following in the earth's crust : (a) Aluminium (b) Calcium ( c) Sodium (d) Lead.

Name the chief forms of the occurrence of the following in the earth's crust : (i) aluminium (ii) calcium (ii) sodium (iv) lead

Phosphorus occurs in nature in the form of stable phosphates. (Animal bones also contain calcuim phosphate (58%)).The important minerals are: (i)Phosphorite, Ca_3(PO_4)_2 (ii)Chloraptite, Ca_3(PO_4)_2CaCl_2 (iii)Fluoraptite, Ca_3(PO_4)_2CaF_2 There are some depoists of nitrates and phosphates in earth's crust.Nitrates are more soluble in water Nitrates are difficult to reduce under the laboratory conditions but microbes do it easily.Compounds of phosphorus and nitrogen are used as fertilizer. Amongs the following which is not member of apatite family ?

Phosphorus occurs in nature in the form of stable phosphates. (Animal bones also contain calcuim phosphate (58%)).The important minerals are: (i)Phosphorite, Ca_3(PO_4)_2 (ii)Chloraptite, Ca_3(PO_4)_2CaCl_2 (iii)Fluoraptite, Ca_3(PO_4)_2CaF_2 There are some depoists of nitrates and phosphates in earth's crust.Nitrates are more soluble in water Nitrates are difficult to reduce under the laboratory conditions but microbes do it easily.Compounds of phosphorus and nitrogen are used as fertilizer. Ca_3(PO_4)_2CaF_2+H_2SO_4to(X)+HF X is -

Name a metal found abundantly in the earth's crust.

Assertion: Sedimentary nutrient cycles of phosphorus, calcium, magnesium, etc., are considered as imperfect Reason: These cycles get more easily disrupted by local disturbances as the bulk of material remains in the relatively inactive and immobile reservoir on the earth's crust.

Name important oxides and oxyacids of nitrogen and phosphorus and write their formulae.

Name : The most abundant elements in the earth's crust .

To what extent is sodium present in the earth's crust?