Chemical changes are irreversible.
A chemical change that could happen at school would be when you have a chemistry experiment and you mix an acid and a base such as mixing hydrochloric acid with sodium hydroxide.
A chemical change that could happen at home would be baking a cake. You can't take the ingredients used in baking a cake back apart because they have changed their chemical composition.
A chemical change that happens in nature could be a forest fire. The burning of wood would be the chemical change in this case.
Answer:
alkenes
nucleophiles
electrophiles
syn
anti
syn and anti
Explanation:
Compounds that contain a carbon-carbon double bond are known as <u>alkenes</u>
Alkenes are electron rich; therefore, simple alkenes do not react with <u>nucleophiles</u> or bases, but will react with <u>electrophiles</u> or acids.
In the IUPAC system, an alkene is identified by the suffix -ene-
Addition reactions in which two parts Of a reagent are added to the same side of
a double bond are known as <u>syn </u>additions.
Addition reactions in which two parts of a reagent are added from opposite
sides of a double bond are called <u>anti</u> additions
Halogenation and halohydrin formation occur with <u>syn and anti</u> -additions.
Further explanations:
Compounds that contain a carbon-carbon single bond are known as alkanes. Compounds that contain a carbon-carbon double bond are known as alkenes. Compounds that contain a carbon-carbon triple bond are known as alkynes.
Nucleophiles are electron rich so they react with electron deficient centers while Electrophiles are electron deficient so they react with electron rich centers.
Answer: Option B) Atom
Explanation:
An atom is the simplest particle of an element that can retain all the chemical properties of the element, and therefore take part in a chemical reaction.
Thus, an atom of zinc (Zn) represent fully the entire properties of elemental Zinc. For instance: an atom of zinc has a mass of 65.38g.
The most viscous liquid between milk, apple juice, water, and syrup will be the syrup. The syrup is the thickest of these choices. A viscous liquid is slower to pour. The thicker the product is the more viscous it is. Water, milk, and apple juice all flow faster than syrup would. The correct answer is A: syrup.
The weighted average of a penny is = 67.9g
<h3>Calculation of average weight</h3>
The sample of penny for pre 1982 is a total of = 18 pennies.
The mass of each penny for pre 1982 = 3.1
Therefore the total weight for penny for pre 1982
= 18×3.1
= 55.8
The sample of penny for post 1982 is a total of = 32 pennies.
The mass of each penny for post 1982 = 2.5
Therefore the total weight for penny for post 1982
=32×2.5
= 80
The weighted average
= 55.8+80/2
= 135.8/2
= 67.9g
learn more about mass here:
brainly.com/question/14156113
#SPJ1
