The Artisans of Igun — Brass Casters and the Secrets They Pass Down
Edwin Ogie Library is a dynamic platform for education, focused on fostering mindful communication and building positive relationships by eliminating linguistic errors. Our mission is to enhance connections through thoughtful language, emotional regulation, and self-awareness, providing educational resources that inspire personal growth. We aim to promote well-being, peace, and meaningful connections, offering a space for individuals committed to refining their communication skills.
Simplify: 34 × 32 ÷ 33
Evaluate: (23)2 × 2-5
Simplify: (53 × 5-2) ÷ 5-1
If xa × xb = x12, find a + b when x = 2.
Simplify: (4/9)-1/2
Express 27x-3y2 in simplified form with positive indices.
Simplify: 32n+1 ÷ 3n-1
If 2x = 8, find x.
Simplify: (43 × 4-2)1/2
Express 1/2-3 in standard form.
Topics: Chemical and Physical Changes, Atoms, Molecules, Elements, Ions, Compounds, Dalton's Atomic Theory, Rutherford and Bohr's Postulates, Isotopes, Relative Atomic Mass, Relative Molecular Mass.
1. Which of the following is a physical change?
A. Burning of paper
B. Melting of ice
C. Rusting of iron
D. Digestion of food
2. An example of a chemical change is:
A. Boiling water
B. Freezing water
C. Burning wood
D. Melting wax
3. Which of the following statements is true about atoms?
A. Atoms are indivisible and indestructible
B. Atoms of the same element differ in mass
C. Atoms are the smallest particles of matter
D. Atoms can be created during chemical reactions
4. The nucleus of an atom contains:
A. Protons and neutrons
B. Protons and electrons
C. Electrons and neutrons
D. Protons only
5. Which scientist proposed the idea that atoms are indivisible?
A. J.J. Thomson
B. John Dalton
C. Ernest Rutherford
D. Niels Bohr
6. According to Rutherford’s model of the atom, the nucleus is:
A. Positively charged
B. Negatively charged
C. Neutral
D. Surrounded by stationary electrons
7. Niels Bohr’s model of the atom explains:
A. The arrangement of protons in the nucleus
B. The arrangement of electrons in orbits
C. The neutrality of atoms
D. The existence of isotopes
8. Isotopes are atoms of the same element that:
A. Have different atomic numbers
B. Have different mass numbers
C. Have different numbers of protons
D. Have the same mass numbers
9. The relative atomic mass of an element is determined by:
A. Adding the masses of protons and electrons
B. The mass of one atom of the element
C. Comparing the element's mass to carbon-12
D. The number of neutrons in the nucleus
10. The relative molecular mass of a compound is:
A. Equal to the atomic mass of the compound
B. The sum of the atomic masses of the elements in the molecule
C. Always greater than 100
D. The mass of a single atom
11. Calculate the relative molecular mass of H2O. (H = 1, O = 16)
A. 18
B. 20
C. 16
D. 12
12. Calculate the number of molecules in 9 g of water (H = 1, O = 16, Avogadro’s number = 6.02 x 1023)
A. 3.01 x 1023
B. 6.02 x 1023
C. 9.03 x 1023
D. 1.20 x 1023
13. Which of these statements is correct about ions?
A. An ion is always positively charged
B. Ions are formed when atoms lose or gain electrons
C. An ion has equal numbers of protons and electrons
D. Ions are electrically neutral
14. The molar mass of CO2 is:
A. 22 g/mol
B. 44 g/mol
C. 28 g/mol
D. 16 g/mol
15. What is the empirical formula of a compound containing 40% carbon, 6.7% hydrogen, and 53.3% oxygen? (C = 12, H = 1, O = 16)
A. CHO
B. CH2O
C. C2H2O
D. C3H6O
16. What is the charge on a sulfate ion (SO4)?
A. -1
B. -2
C. +1
D. +2
17. Which of the following substances is a compound?
A. Nitrogen
B. Oxygen
C. Water
D. Diamond
18. Calculate the number of moles in 88 g of CO2. (C = 12, O = 16)
A. 2 moles
B. 4 moles
C. 1 mole
D. 0.5 moles
19. Which of the following postulates is part of Dalton's atomic theory?
A. Atoms can be destroyed in chemical reactions
B. Atoms combine in simple whole-number ratios to form compounds
C. Atoms of different elements have the same properties
D. Atoms of the same element have different masses
20. An example of an isotope is:
A. Carbon-12 and Carbon-14
B. Oxygen and Nitrogen
C. Sodium-23 and Magnesium-24
D. Hydrogen and Helium
1. Which of the following is a fundamental quantity?
2. The unit of acceleration is:
3. A car travels 120 km in 3 hours. What is its average speed?
4. Displacement is an example of a:
5. The SI unit of force is:
6. Which of the following represents a derived quantity?
7. A body moves with a velocity of 15 m/s for 10 seconds. What is the total distance covered?
8. Which of these laws is used to find the resultant of two forces acting at an angle?
9. A vector quantity has:
10. Resolve a force of 50 N acting at an angle of 30° into its horizontal component.
Comments
Post a Comment
We’d love to hear from you! Share your thoughts or questions below. Please keep comments positive and meaningful, Comments are welcome — we moderate for spam and civility; please be respectful.