Answer:
2HI + K2SO3=>2KI+H2SO3
Explanation:When aqueous hydroiodic acid and aqueous potassium sulfite are mixed the products obtained are potassium iodide and sulfurous acid.Both reactants are ionic compounds and they undergo double replacement reaction.In a double replacement reaction the parts of the ionic compounds are changed.The product is obtained by combinig cation of one compound with anion of other compound.so in above reaction sulfurous acid is obtained which is in gaseous form and potassium iodide is an ionic compound.
Answer:
Burning of paper is not a physical change.It is chemical change as ash is formed in the process which is new compound and oxides of carbon are also released during the process!
The concentration of NaOH is 25.00% by mass, it means that 25.00% of the mass of the solution is of NaOH. Hence:
freezing-energy lost (exothermic)
sublimation-energy gain (endothermic)
evaporation- energy gain(endothermic)
Melting- energy gain(endothermic)
deposition- energy lost(exothermic)
condensation-energy lost(exothermic)
Answer:
no of moles = (mass) ÷ molar mass
you get the molar mass from the periodic table
n = 20.0g ÷ ( 149.09 g/mol )
= 0.134 mol
number of formula units = number of moles × (6.022×10^23)
= 8.07×10^22 units
number of hydrogen atoms in (NH4)3 PO3 = 12 × number of formula units
= 9.68×10^23 hydrogen atoms