1st quarter

Question 1

Water molecules in ice have greater distances between them making their densies
lower than that of liquid water, therefore, what will happen to ice cubes in liquid water?

Answer 1

Ice will float on liquid water.

Question 1

Where does hydrogen-bond exist in the following substances?

Answer 1

. Water

Question 2

Which IMFA is responsible why salt dissolves in water?

Answer 2

Ion-Dipole

Question 3

In which process light elements got formed during the Big Bang?

Answer 3

Fusion reaction

Question 4

How were elements heavier than iron formed?

Answer 4

Neutron capture reaction takes place leading to the formaon of heavy elements.

Question 5

Which type of elements are formed during supernovas?

Answer 5

Heavy elements

Question 6

What is the first stage of star evoluon?

Answer 6

Protostar

Question 7

Which element was not produced during the Big Bang?

Answer 7

. Carbon

Question 7

How is star energy produced?

Answer 7

By nuclesr Fusion

Question 8

Who created a classificaon of elements based on their atomic weight?

Answer 8

Mendeleev

Question 9

When does a star become unstable?

Answer 9

When it runs out of fuel

Question 9

Which is not an evidence of the Big Bang?

Answer 9

Expansion of the Universe

Question 10

Which of the following gases are major components of stars?

Answer 10

Hydrogen and helium

Question 10

What is the consequence if Neils Bohr’s energy shells didn’t exist?

Answer 10

The electrons would have been compacted with the protons in the nucleus.

Question 11

Which of the following describes a Hydrogen Bond?

Answer 11

H-atoms aached to O, N, F atoms

Question 12

What can be deduced when alpha particles passed through the gold foil in Rutherford’s experiment?

Answer 12

The atom is empty space while the nucleus is posively charged

Question 13

What is true if Neils Bohr’s energy shells didn’t exist?

Answer 13

The electrons would have been compacted with the protons in the nucleus.

Question 14

Why are elements with atomic numbers 93 to 118 called transuranic?

Answer 14

Because their atomic numbers are higher than uranium

Question 15

What will result in an interaction between the H-atom in a polar bond and an
electronegave atom such as O, N, or F?

Answer 15

H-bonding

Question 16

Which is not an example of a viscous substance?

Answer 16

Vinegar

Question 17

Who successfully carried out a nuclear transmutaon reacon, the process of transforming one element
or isotope into another element?

Answer 17

Rutherford

Question 18

What is true about intermolecular forces?

Answer 18

Substances can form more than ones, but one will predominate

Question 19

Which of the following is a polar bond?

Answer 19

H—C

Question 20

Which of the following is a non-polar covalent bond when comparing their electro-negatives?

Answer 20

.CH4

Question 21

Why do water molecules have high boiling points?

Answer 21

It is a polar molecule.

Question 22

Which statement is correct about catalysts?

Answer 22

A substance which speeds up a reaction but is chemically unchanged

Question 23

What is the amount of catalyst needed for chemical reactions to happen?

Answer 23

Small amount

Question 24

How many numbers of elements are on one side of an equation to the opposite side?

Answer 24

. Same

Question 25

What is the attraction of a positively and a negatively charged ion?

Answer 25

. Ion-Ion

Question 26

What is the classification of these strong and durable materials which are used as substitutes for missing or injured body parts?

Answer 26

Medical Implants

Question 27

Which materials are used in the design and manufacture of household appliances and gadgets?

Answer 27

Electronic devices

Question 28

Which could be used as a biomedical material for breast implants because of its ion–dipole IMFA?

Answer 28

Silicone

Question 29

What is the priority in the design of sports equipment regardless of its specific purpose?

Answer 29

Biomechanic, Physics, Engineering Are Correct.

Question 30

What is the purpose of cellulose, a carbohydrate as a component of a plant cell wall?

Answer 30

It contributes to its rigidity.

Question 31

Which of the following is a carbohydrate?

Answer 31

Sucrose

Question 32

Which one is a lipid?

Answer 32

Triglyceride

Question 33

What is true when comparing the degree of activation energy of 100 ml of water to that of 100 ml of alcohol heated at the same temperature?

Answer 33

Water has lower acvaon energy

Question 34

What will result in an increase in reaction rate?

Answer 34

More molecules that can overcome the acvaon energy

Question 35

What is the percent yield if the theoretical yield is 0.25 mol of SiCl4 if in the lab only 0.20 mol of SiCl4 were produced?

Answer 35

80%

Question 36

What is the reason for the changes in the energy involved in chemical reactions.?

Answer 36

Breaking and formation of bonds

Question 37

Which one is an endothermic process?

Answer 37

. Ice cubes melng

Question 38

A reaction is allowed to take place in an insulated container containing 100 mL of water. If the reaction is exothermic, what happens to the temperature of the water?

Answer 38

The temperature of the container goes up

Question 39

Which of the following is not a factor affecting rate of chemical reactions?

Answer 39

Action of catalysts

Question 40

Biomass refers to organic matter from plants and animals. From the choices below, which source follows this definition?

Answer 40

. Crop Remains

Question 41

Which of the following is amaterial for personal care?

Answer 41

toothpaste

Question 42

Which of the following compounds is biogas primarily made of?

Answer 42

. Carbon dioxide and methane

Question 43

How is heat from inside the earth tapped as a source of energy for human use?

Answer 43

Chemical energy can be converted to electrical.

Question 44

How does muriac acid remove dirt and grime from toilets and sinks?

Answer 44

. It is a strong acid and can dissolve mineral buildup.

Question 45

The precautionary measure included in the product reads, “keep out of reach of children”. What does it tell you ahead?

Answer 45

. It may contain chemicals harmful to children.