How many grams of calcium hydride are needed to form 4.850 g of hydrogen gas? express your answer using four significant figures?

The number of  calcium hydride that are needed to form 4.850 g of hydrogen gas =101.85 grams

calculation

write the equation for decomposition of CaH2

that is CaH2→ Ca +H2

find the moles of H2 produced = 4.850/2 =2.425 moles

by use of mole ratio between CaH2:H2 which is 1:1 the moles of CaH2 is also 2.425 moles

mass of CaH2 is therefore = moles x molar mass

= 2.425 moles x 42 g/mol= 101.85 grams

answer: e.   sour taste

explanation: acids are those substances which dissociates in water to give ions. as they dissociate to give ions, they act as electrolytes and thus are electrically conductive. acids are sour in taste. example: hcl

bases are those substances which dissociates in water to give ions or accepts ions. as they dissociate to give ions, they act as electrolytes and thus are electrically conductive. bases are bitter in taste. bases are slippery in nature.

particle   p is an electron and particle q is a neutron