Helium is expressed as —

এই অধ্যায়ের আরও প্রশ্ন

• C-05-Q056Valency of Al = 3 and O = 2; the formula of aluminum oxide is —
• C-05-Q057Formula of calcium chloride (Ca = 2, Cl = 1) is —
• C-05-Q058Formula of magnesium phosphate (Mg = 2, = 3) is —
• C-05-Q059Formula of ammonium phosphate is —
• C-05-Q060Formula of aluminum sulfate is —
• C-05-Q061When valencies share a common factor, divide by it; for C (4) and O (2), the formula becomes —
• C-05-Q062Formula of ferrous sulfate (Fe = 2, = 2) is —
• C-05-Q063Formula of boron nitride (B = 3, N = 3) is —
• C-05-Q064When a radical appears more than once in a formula, it is enclosed in —