Subject: Bio - Chemistry

#25

Which is a characteristic of a chemical change?

A) Change in state

B) Reversible

C) Formation of new substance

D) No energy change

Answer:   C

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#26

Which bond is formed between oppositely charged ions?

A) Covalent

B) Ionic

C) Hydrogen

D) Metallic

Answer:   B

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#27

Which one is a product in the reaction: HCl + NaOH ? NaCl + ?

A) H2

B) O2

C) H2O

D) CO2

Answer:   C

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#28

Which element is necessary for hemoglobin in blood?

A) Calcium

B) Sodium

C) Iron

D) Potassium

Answer:   C

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#29

Which of the following is an acid?

A) NaCl

B) H2O

C) HNO3

D) CH4

Answer:   C

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#30

Which is NOT a state of matter?

A) Gas

B) Plasma

C) Energy

D) Liquid

Answer:   C

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#31

Which one is a polyatomic ion?

A) Na?

B) Cl?

C) SO4²?

D) K?

Answer:   C

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#32

Which of these is a symbol of a chemical element?

A) NaCl

B) H2O

C) CO2

D) O

Answer:   D

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