Answer:
Atomic mass is the mass of an atom and is given in a.m.u. (atomic mass unit).
Explanation:
Atomic mass is the mass of an atom and is given in a.m.u. (atomic mass unit). However, a molar mass is the mass of one mole atoms or molecules and is given in grams. Sodium atom has a mass of 23 a.m.u. however, the molar mass of sodium is 23g/mol.
1) Chemical equation
<span>2NH4Cl(s)+Ba(OH)2⋅8H2O(s)→2NH3(aq)+BaCl2(aq)+10H2O(l)
2) Stoichiometric ratios
2 mol NH4Cl(s) : 54.8 KJ
3) Convert 24.7 g of NH4Cl into number of moles, using the molar mass
molar mass of NH4Cl = 14 g/mol + 4*1 g/mol + 35.5 g/mol = 53.5 g/mol
number of moles = mass in grams / molar mass
number of moles = 24.7 g / 53.5 g/mol = 0.462 moles
4) Use proportions:
2 moles NH4Cl / 54.8 kJ = 0.462 moles / x
=> x = 0.462 moles * 54.8 kJ / 2 moles = 12.7 kJ
Answer: 12.7 kJ
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Answer : Option B) A Comet
Explanation : A comet is mainly composed of rock, dust, ice and frozen gases like carbon monoxide, carbon dioxide, methane, and ammonia. It is sometimes called as dirty snowballs, recent studies on comets have revealed that the ice of a comet is covered by a crust. Comets also contain many variety of organic compounds as well as the gases.
Comets when comes near the sun while revolving around it loses some of the ice from its crust which gets vaporized by sun's heat.
Batteries can convert stored chemical energy into electrical energy In a flashlight, the electrical energy becomes light energy and thermal energy in the bulb