Answer:
D: a new substance
Explanation:
Chemical reaction
A change in matter that produces on or more new substances
Explanation:
The word equation for the burning of a candle is wax plus oxygen yields carbon dioxide and water. This is an exothermic reaction that produces both light and heat.
The fuel for a burning candle is the wax. There are many different types of wax with a corresponding number of chemical formulas, but they are all hydrocarbons. Hydrocarbons are molecules made from hydrogen and carbon.
Burning the wax pulls the hydrogen and carbon in the wax apart and recombines them with oxygen from the atmosphere. This is an oxidation reaction. The resulting carbon dioxide and water are gases that disperse in the air.
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Answer:
mass PbI₂ formed = 1383 grams
Explanation:
Pb(NO₃)₂ + 2NaI => 2NaNO₃ + PbI₂(s)
6 mol NaI => 1/2(6 mol) PbI₂ = 3 mol PbI₂ x 461.01 g/mol = 1383.03 grams ≅ 1383 grams (4 sig. figs.)
The 2 sources are solar and nuclear energy.
The significance of melting points are
- it gives us a idea about inter molecular force which binds the particles together.
- at melting point the solid and liquid states exist in equilibrium.
<h3>What is melting point?</h3>
The melting point is the temperature at which a given substance change its physical state from solid to liquid. At this point solids and liquids exist at equilibrium. Melting point of a substance depends on pressure. The melting point of ice increases when pressure decreases. Melting point of a substance decreases by the presence of impurities in it. so you increase or decrease the melting point on any substance by adding more impurities. Ionic bonds, shape and size of molecules are some other factors that affect the melting point.
To learn more about melting point refer:
brainly.com/question/25689052
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