Chemistry EUEE 2004 E.C Grade 11 Unit One

What is the number of moles of atoms and number of atoms in a 10.0-g sample of copper?

• 0.08 mol Cu atoms and 2.16 x 10^23 atoms

• 0.16 mol Cu atoms and 9.63 x 10^22 atoms

• 0.16 mol Cu atoms and 9.63 x 10^23 atoms

• 0.31 mol Cu atoms and 4.16 x 10^23 atoms

How many atoms are present in 22g CO2?

• 3.01 x 10^23

• 6.02 x 10^23

Which electron transition in a hydrogen atom releases the largest energy?

• n = 2 to n = 1

• n = 4 to n = 2

• n = 6 to n = 3

• n = 7 to n = 6

What is the ratio of the energy of a photon of 300nm wavelength radiation to that of 600nm radiation?

• 1:2

• 1:1

• 2:1

• 3:1

Which of the following particles contains more electrons than neutrons?

• I only

• II only

• I and II only

• II and III only

Which one of the following atoms in its ground state has the greatest number of unpaired electrons?

• 13Al

• 14Si

• 15P

• 16S

What is the ionization energy of an iron atom if it requires a radiation of 276 nm to completely remove its outermost electron in the gaseous state? (Planck's constant, h = 6.626 x 10^-34 Js, speed of light, c = 3 x 10^8 m/s)

• 7.21 x 10^-19 J

• 7.21 x 10^-19 kJ

• 7.21 x 10^19 J

• 7.21 x 10^19 kJ

Which of the electron configurations describes the ground state electron configuration of Cl1?

• 1s2 2s2 2p6 3s2 3p6

• 1s2 2s2 2p6 3s1

• 1s2 2s2 2p6 3s2 3p x 2 3p y 1

How many 3d electrons are present in the ground state of chromium atom?

• 4

• 5

• 6

• 10

Of the three types of radioactivity characterized by Rutherford, which of the following are particles?

• alpha rays

• beta rays and gamma rays

• beta rays

• alpha rays, beta rays, and gamma rays