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2 years ago

Please help!

Chemistry

2 answers:

ANEK [815]2 years ago

8 0

Answer:

A- Physical, B- Chemical, C- chemical, D- Physical

Explanation:

A is physical because you can see it changing its form is changing.

B is Chemical because a new substance is formed creating the orange color of rust.

C is a Chemical reaction because it is being broken down so the banana itself is changing not just how we see it.

D is physical because we are just changing the shape/ size of the item, not anything to do with its substances.

motikmotik2 years ago

8 0

Answer:

a. physical change, it is reverse reversible since no new substance is created.

b.chemical change, The iron reacts with water and oxygen to form hydrated iron(III) oxide, which we see as rust.

c. chemical change, Bananas contain compounds known as polyphenol oxidases and iron-containing chemicals. These chemicals react with oxygen to turn the fruit brown.

d. physical change, there is no new substance created, and there is no change in the original composition of wood.

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The key enzyme in the regulation of the citric acid cycle is:.

bixtya [17]

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A 1.42-g sample of a pure compound with formula m2so4 was dissolved in water and treated with an ex- cess of aqueous calcium chl

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Thus, 9.989× $10^{-3}$ moles of $m_{2}SO_{4}$ reacts in this reaction.

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Or, 2x = 46.146

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3 years ago

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2 years ago

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notsponge [240]

Answer:

Option C. hydroxide ions (OH-).

Explanation:

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