<span>When water freezes, the molecules move farther apart. </span>
Answer: A. Exothermic reaction
Explanation: Enthalpy change for a reaction is sum of enthalpy of formation of products minus sum of enthalpy of formation of reactants.
When the energy level of reactants is above as compared to the products, the reaction is exothermic and when its opposite then reaction is endothermic.
From given information, the potential energy diagram starts at 380 kJ means the energy level of reactants is 380 kJ. It ends at 100 kJ means the energy of products is 100 kJ.
Enthalpy of reaction = 100 kJ - 380 kJ
Enthalpy of reaction = -280 kJ
Negative sign of enthalpy change indicates an Exothermic reaction.
The three particles found in an atom are the protons, neutrons and electrons. Protons have a positive charge. Electrons have negative charge. Lastly, neutrons have no net electrical charge. Protons and neutrons are much heavier than electrons and are located in the center of the atom.
Answer:
D. A solution.
Explanation:
"Water molecules pull the sodium and chloride ions apart, breaking the ionic bond that held them together. After the salt compounds are pulled apart, the sodium and chloride atoms are surrounded by water molecules, as this diagram shows. Once this happens, the salt is dissolved, resulting in a homogeneous solution."
<span>Ammonia (NH3) is the combination of Nitrogen and Hydrogen
elements.
=> N2 + 3H2 => 2NH3
Ammonia is basically used as a fertilizer. It is a gas composed of nitrogen and
hydrogen. It is colorless with strong odor. Here are some other uses of Ammonia
aside from fertilizer:
=> used by manufacturer to produce synthetic fiber
=> Used in metallurgical process
Ammonia can be decomposed easily and it produce hydrogen that is very
convenient in welding.
Ammonia’s boiling point is -28.03 F and freezing point is -107.8F.
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