Answer:
A catalyst speeds up a chemical reaction
Explanation:
It increases the reaction rate by lowering the activation energy for a reaction.
Answer: 10 cm3
Explanation:
Mass of sample of steel (m) = 80 grams
density of sample of steel (p) = 8 g/cm3 samples volume (v) = ?
Since density is obtained by dividing mass by volume, the density of the steel sample is expressed as:
density = mass / volume
p = m / v
make v the subject formula
v = m / p
v = 80 grams / 8 g/cm3
v = 10 cm3
Thus, the samples volume is 10 cm3
Always remember that a compound can be separated into simpler substances by chemical methods/reactions. While elements cannot be broken down into simpler substances by chemical reactions. You can do a flame test and spectrum analysis to determine whether a solid material is an element or a compound. Check the boiling and/or melting point, color or density. Also check the solid material’s reaction with oxygen, hydrogen, calcium, or various acids. Examine and study its physical chemistry. The element(s) that may be present may be identified by checking the absorption edges from an x-ray spectrum.
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Option-C: They react mainly by substitution.
Explanation:
Alkene doesn't give substitution reactions because they are non polar in nature. The double bond in alkene is responsible for Electrophillic Addition reactions as it electron rich and nucleophilic in nature. Reaction of Alkene is given below,</span>
Potential energy and height; best guess;)