Answer:
382.5J
Explanation:
<em>Use the formula:</em>
E = mcΔθ or Q = mcΔT
m = 100g
c = 0.45 J/g°C
ΔT or Δθ = 110 - 25 = 85°
<em>Sub in the values:</em>
E = 100 × 0.45 × 85
= 382.5J
Answer:
B) As you move across the row, the number of electrons increases and reactivity also increases.
Explanation:
The periodic table is arranged in a way that if you go across a period, the number of protons, neutrons, and electrons in an element increases. In terms of reactivity, the most reactive elements are the ones which have a high electronegativity. The electronegativity of the elements increases as you travel to the right and upwards on the periodic table.
Answer:
C. Dry the methylene chloride by removing water
Explanation:
Anhydrous sodium sulfate is known for its high capacity to absorb water, for this reason it is widely used in laboratories as a drying agent.
Sodium sulfate is a neutral molecule so it cannot be used to neutralize and is very stable, so it is difficult to precipitate organic molecules.
Answer:
Water, H2O, is a pure substance, a compound made of hydrogen and oxygen. Although water is the most abundant substance on earth, it is rarely found naturally in its pure form. Most of the time, pure water has to be created. Pure water is called distilled water or deionized water.
Answer:
chemical
Explanation:
The chemical properties determine the identity of a substance and are not changed when there is no reaction. In the solution, what takes place is a physical change, which is a change of state (for example, going from solid to aqueous form).