1. Energy required to remove an electron from gaseous neutral atom is:A. Electron affinityB. Lattice energyC. Ionization energyD. Crystal energy 2. The elements for which the value of ionization energy is low can:A. Gain electrons readilyB. Gain electrons with difficultyC. Lose electron less readilyD. Lose electron readily 1. Energy required to remove an electron from […]
The s & P Block Elements Read Post »
1. What is the correct IUPAC name for the given alkyl halide, CH3CH2CH(C2H5) CH2CH(I)CH2CH3?A. 5-Iodo-3-ethylheptaneB. 3-Iodo-5-ethylheptaneC. 5-Ethyl-3-iodoheptaneD. 3-Ethyl-5-iodoheptane
Alkyl Halides (Halogenoalkanes) Read Post »
1. Consider the chlorination of methane to methyl chloride. The attack of a chlorine free radical on methane occurs in which phase?A. Before initiationB. InitiationC. PropagationD. Termination 2. A patient with pancreatic insufficiency shows reduced activity of an enzyme that hydrolyzes the peptide bond at the carboxyl end of proteins and peptides. Which enzyme is
KMU MDCAT Paper 2025 Read Post »
1. Two elements X and Y have the following electronic configurations:X: 1s2 2s22p6 3s2 3p1Y: 1s2 2s2 2p4Which compound are these elements most likely to form?A. X2YB. X3Y2C. X2Y3D. XY3 2. Which particles are directly involved in ordinary chemical reactions?A. ProtonsB. NeutronsC. ElectronsD. Electron, protons, and neutrons 3. In cathode-ray experiments, the same type of
1. When 4 moles of solid potassium chlorate (KClO3) are heated until it fully decomposes, how many moles of oxygen gas (O2) are produced? 2KClO3 → 2KCl + 3O2 A. 5 moleB. 2 molesC. 12 molesD. 6 moles 2. Which of the following samples contains exactly one mole of molecules? A. 4 gram of
Redox Reactions: Oxidation, Reduction, and Everything You Need to Know Why Your Phone Battery, Rusty Iron, and a Cut Apple All Share One Idea Think about three everyday things: a freshly cut apple slowly browning on your kitchen counter, an iron railing turning orange-red after weeks of rain, and a smartphone battery quietly powering your
1. Two elements X and Y have the following electronic configurations:X: 1s² 2s² 2p⁶ 3s² 3p¹Y: 1s² 2s² 2p⁴Which compound are these elements most likely to form?A. X₂YB. X₂Y₂C. X₂Y₃D. XY₃ 2. Which set of molecules follows the correct order of bond angle from largest to smallest based on VSEPR Theory ? A. AX₂ > AX₃
Greek Philosophers’ Concept of Matter Greek philosophers believed that everything in the universe is made of a basic substance called an element. Some thought that this element was water, while others believed it was air. They tried to explain the nature of matter using simple ideas, although these were not based on experiments. Corpuscular Theory
Chemistry and Its Branches Read Post »
The term organic comes from a Greek word organikos which means “related to organ”. In 1808, the Swedish chemist Jons Jacob Berzelius proposed a theory known as the Vital Force Theory. According to this theory, organic compounds contained a spiritual force, called vital force, which is present in plants and animals. He believed that they
Modern periodic table is the systematic arrangement of elements based on increasing atomic number. The formation of this periodic table is not a matter of months or years. It took centuries to evolve. History of Periodic Table From the beginning of human history till 17th century, humans knew only a dozen of elements like gold,
Atomic structure builds the foundation of chemistry because it explains the composition, behaviour, and interactions of matter at the smallest level. All substances, living or non-living, are made up of atoms—the basic units of matter. Understanding the structure of atom helps explain chemical reactions, bonding, periodic trends, and the properties of elements. The concept of
