Answer:
Coal is classified as a nonrenewable energy source because it takes millions of years to form. Coal contains the energy stored by plants that lived hundreds of millions of years ago in swampy forests.
Answer : The correct option is, (2) Cr (Chromium)
Explanation :
The reactivity series of metal are arranged of the reactivity from the highest to the lowest. Reactivity series is used to determine the products of the single displacement reactions. In the single displacement reaction, the most reactive metal displaces the least reactive metal.
From the given reactivity series we conclude that there are two metal (Mg and Cr) are more reactive metal than the Ni and there are two metal (Pb and Cr) are less reactive metal than the Zn. So, the Cr (Chromium) is the metal which is more active than Ni and less active than Zn.
Hence, the correct option is, (2) Cr
Oxygen is balanced incorrectly.
The correct balanced equation: 2C6H6+15O2=12CO2+6H2O
The volume of the piece of aluminum is 1.96 mL
Explanation:
Density is the relationship of the mass of a substance and its volume.
In this case, the mass of aluminum is 5.30 g and the density is 2.70 g/mL
The formula to apply is;
D=M/V where D is density in g/mL, M is mass in g and V is volume in mL
2.70=5.30/V
V=5.30/2.70 =1.96 mL
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Density of a substance:brainly.com/question/12605423
Keywords: volume, aluminum,density
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