Question

1. What is the state of water at room temperature?

a. Solid
b. Liquid
c. Gas
d. Plasma


2. An ion is a charged particle that is formed when
a. An atom gains electrons
b. An atom loses electrons
c. Both A and B
d. None of the above


3. A gas can be referred to as having:
a. Indefinite volume and shape
b. Definite shape and volume
c. Indefinite shape and definite volume
d. Indefinite volume and definite shape


4. What is the change of state from a solid directly to a gas called?
a. Condensation
b. Evaporation
c. Both a and b
d. Sublimation


5. What is matter?
a. A change of state
b. Anything that has mass and takes up space
c. Both a and b
d. None of the above


6. A particle with a positive charge is referred to as a
a. neutron
b. electron
c. proton
d. anion


7. An atom of Sodium has 11 protons and a mass number of 23. How many neutrons does it have?
a. 11
b. 34
c. 14
d. 12


8. An atom in its lowest energy configuration is said to be in
a. Rest state
b. Dormant state
c. Ground state
d. Low state


9. The type of reaction where two of more simple compounds combine to form a more complicated one is
a. Combustion reaction
b. Decomposition reaction
c. Synthesis reaction
d. Displacement


10. According to Dalton's Atomic Theory
a. Atoms of difference elements all have the same size and mass
b. Atoms of difference elements all have the same size but different mass
c. Atoms of different elements differ in size and mass
d. None of the above


11. Electrons closer to the nucleus are _________ in energy than electrons further away.
a. Moderately higher
b. Lower
c. Significantly higher
d. Both a and c


12. What is the maximum electron capacity of the "s" orbital of an atom?
a. 2
b. 6
c. 10
d. 14


13. The smallest particle of an element that still retains the characteristics of that element is called
a. Element
b. Anion
c. Cation
d. Atom


14. The symbol for the element Copper is
a. Cu
b. C
c. Ca
d. Pb


15. On the periodic table, horizontal rows are known as __________ and vertical columns are known as ______________.
a. metals, non metals
b. groups, periods
c. halogens, alkalis
d. periods, groups


16. ______________ are usually good conductors of heat and electricity, while ___________ are usually poor conductors of heat and electricity.
a. Non- metals, metals
b. Metals, non-metals
c. Halogens, alkaline earth metals
d. Noble gases, halogens


17. Which of the four elements has the highest electronegativity?
a. F
b. P
c. Li
d. Cl


18. The compound NaCl is an example of a/an
a. Covalent bond
b. Ionic bond
c. Metallic bond
d. None of the above


19. A compound that conducts electricity when dissolved in water is knows as
a. A non-electrolyte
b. An electron
c. An insulator
d. An electrolyte


20. The mass percents for the elements present in H2SO4
a. H-32.6% S-65.3% O-2.06%
b. H-2.06% S-32.6% O-65.3%
c. H-2.06% S-32.6% O-56.3%
d. H-2.00% S-40% O-58%


21. Determine the empirical formula for a compound that contains 3.238 g sodium, 2.265 g sulfur, and 4.499 g oxygen.
a. Na2SO4
b. NaSO
c. NaS2O2
d. NaO


22. C10H8 + 12O2 ---> 10CO2 + 4H2O

This reaction represents a

a. Displacement reaction
b. Synthesis reaction
c. Combustion reaction
d. None of the above


23. The salt formed from the Acid/ Base reaction between HBr and NaOH is called
a. Sodium Bromide
b. Sodium Monobromide
c. Nitrogen Bromide
d. Sodium Bromate


24. Balance the following equation by choosing the correct coefficient for each compound:

__H3PO4 + __Mg(OH)2 ---> __Mg3(PO4)2 + __H2O

a. 1,2,3,4
b. 4,6,5,2
c. 2,3,1,6
d. 3,4,1,3

Answer 1

1. B. Liquid
2. C. both A & B
3. C. Indefinite shape and definite volume
4. D. Sublimation
5. Its gotta either be B or D its most likely D
6. A. Neutron
7. D.12
8. C. Ground State
9. C. Synthesis reaction
10. D. None of the above
11. Both A and C
12. A. 2
13. A. Element
14. A. Cu
15. D. Periods, Groups
16. B. Metals, Non-metals
17. A. F
18. D. None of the above
19. Either B or D
20. B. H-2.06% S-32.6% O-65.3%
21. A. Na2SO4
22. C. Combustion reaction
23. if I'm correct it should be C. Nitrogen Bromide
24. Sorry not sure what the answer is but your welcome I hope the rest of theses help!!

Answer 2

Answer 1: The correct answer is option b.

Explanation: At room temperature that 25 °C water is present as in its liquid state. Water exists as solid on 0 °C and below and as gas on 100 °C and above.

Answer 2: The correct answer is option c.

Explanation:An ion is formed when an atom either gains electrons(anion) or loose electrons(cation).

Answer 3:The correct answer is option c.

Explanation: Gas is one of the state of matter which has no definite shape and size.It takes the shape and size of the container in which it is kept. But gas have definite volume.

Answer 4: The correct answer is option d

Explanation: Sublimation is defined as the process of the conversion of matter from solid state to gaseous state directly by escaping liquid state.

Answer 5: The correct answer is option b.

Explanation: Matter is defined as anything which occupies some space and has mass.

Answer 6:The correct answer is option c

Explanation: The particle with positive charge is called proton. Where as particle with negative charge is called electrons and particle with no charge is called neutron.

Answer 7: The correct answer is option d.

Explanation: Mass number = Number of protons + Number of neutrons

24 = 11 + number of neutrons

Number of neutrons = 12

Answer 8: The correct answer is option c.

Explanation: Electron are not stationary they are all time moving. so, when the electrons moving in their lowest energy configuration they are said to be ground state

Answer 9: The correct answer is option c.

Explanation: Synthesis reaction is defined as those chemical reactions in which two or more than two reactants reacts together to form single product.

A+B+C →D

Answer 10: The correct answer is option c.

Step-by-step explanation:

Dalton's Atomic Theory

• An atom is an indivisible and smallest unit of matter.
• Atom of same element have similar mass and size.
• Atoms of different elements differ in size and mass
• Chemical reaction means change in arrangement of atoms.

Answer 11: The correct answer is option c.

Explanation: Electron near the nucleus experiences stronger electrostatic forces due to which they posses significantly higher energy than electrons further away.

Answer 12: The correct answer is option 2.

Explanation: The maximum electron capacity of s orbital is 2.

Where as for p orbital it is 6, for d orbital it is 10 and for f orbital it is 14.

Answer 13: The correct answer is option d.

Explanation: An atom retains all the properties of its respective element.

Answer 14: The correct answer is option a.

Explanation: Symbol of copper is Cu.

C is for carbon, Ca is for calcium and Pb is for lead.

Answer 15: The correct answer is option d.

Explanation: Horizontal rows are called period and vertical columns are called group.

Answer 16: The correct answer is option b.

Explanation:

Metals are good conductor of electricity and heat due to presence of metallic bonding . Where as in non metal covalent bonding is present.

Answer 17: The correct answer is option a.

Explanation: Electronegativity is defined as the ability to attract the shared pair of an electrons towards itself in bond.

Fluorine being smallest in size and valence electrons are closer to nucleus due to which gain of an electron becomes easier.

Answer 18: The correct answer is option b.

Explanation: Ionic bond is the chemical bond in which complete transfer of electron takes place from one atom to another

Answer 19: The correct answer is option d.

Step-by-step explanation:

An electrolyte those compound which when dissolved in water dissociates into ions and make the solution electrical conducting in nature.

Answer 20: The correct answer is option b.

Step-by-step explanation:

`H\%=(2 g/mol)/(98 g/mol)* 100=2.06 \%`

`S\% =(32 g/mol)/(98 g/mol)* 100=32.6 \%`

`O\% =(64 g/mol)/(98 g/mol)* 100=65.3 \%`

Answer 21: The correct answer is option a.

Step-by-step explanation:

Moles of sodium =
`(3.238 g)/(23 g/mol)=0.1407 moles`

Moles of Sulfur=
`(2.265 g)/(32 g/mol)=0.0707 moles`

Moles of oxygen =
`(4.499 g)/(16 g/mol)=0.2811 moles`

Divide number of moles of every element with smallest value of number of moles.

`Na=(0.1407)/(0.0707)=1.99\approx 2`

`S=(0.0707)/(0.0707)=1`

`O=(0.2811)/(0.0707)=3.9\approx 4`

The empirical formula is
`Na_2SO_4`

Answer 22: The correct answer is option c.

Step-by-step explanation:

Combustion reaction is the burning of organic substance in presence of oxygen gas with release of water , carbon-dioxide ans heat.

Answer 23: The correct answer is option a.

Step-by-step explanation:

`HBr+NaOH\rightarrow NaBr+H_2O`

Sodium bromide NaBr.

Answer 24: The correct answer is option c.

Step-by-step explanation:

`2H_3PO_4+3Mg(OH)_2\rightarrow Mg_3(PO_4)_2+6H_2O`