a) chemical energy
b) by electricity
c)
(i) Light
(ii) thermal transfer
<em>By </em><em>Benjemin</em>
Answer:
1.023 J / g°C
Explanation:
Mass, m = 37.9 g
Temperature increase (change) = 25.0°C
Heat = 969 J
Specific heat capacity , c= ?
The relationship between these quantities is given by the equation;
H = mcΔT
c = H / mΔT
c = 969 / (37.9 * 25)
c = 969 / 947.5 = 1.023 J / g°C
A chemical change
Explanation:
In this reaction, a chemical change has occurred, here are some indicators of chemical changes from the reaction;
Chemical changes are changes in which new products are formed.
- Formation of bubbles and precipitates: these are new substances that indicates a chemical change. The bubbles and insoluble precipitate are good indicators of chemical change.
- A temperature change that is large; This is also typifies chemical changes. When temperature rises in reaction, a chemical change has occurred.
- The bubbles and precipitates cannot be combined to give the reactants. The reaction is irreversible.
learn more:
Chemical change brainly.com/question/9388643
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A) Cu
Cu + 2HCl --> CuCl2 + H2(g)
Products predicted: Copper(II) choloride and hydrogen gas
B) Mg
Mg + 2HCl --> MgCl2 + H2
Products predicted: magnesium chloride + hygrogen gas
C) Fe
Fe +2 HCl -> FeCl2 + H2, or
2Fe +6 HCl -> 2FeCl3 + 3H2
Products predicted: Iron(II) chloride, iron (III) chloride and hydrogen gas.
2Al+6HCl⇒3H₂+2AlCl₃
<h3>Further explanation
</h3>
Equalization of chemical reaction equations can be done using variables. Steps in equalizing the reaction equation:
• 1. gives a coefficient on substances involved in the equation of reaction such as a, b, or c etc.
• 2. make an equation based on the similarity of the number of atoms where the number of atoms = coefficient × index between reactant and product
• 3. Select the coefficient of the substance with the most complex chemical formula equal to 1
Reaction
Al+HCl⇒H₂+AlCl₃
aAl+bHCl⇒cH₂+AlCl₃
Al, left=a, right=1⇒a=1
Cl, left=b, right=3⇒b=3
H, left=b, right=2c⇒b=2c⇒3=2c⇒c=3/2
the equation becomes :
Al+3HCl⇒3/2H₂+AlCl₃ x2
2Al+6HCl⇒3H₂+2AlCl₃