NPCIL Trainee The Chemical Foundation of Life — practice questions
21 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice NPCIL Trainee The Chemical Foundation of Life in the app →In chemistry and biology, "matter" is defined as:There are 118 known chemical elements. How many of these occur naturally?Isotopes of the same element are atoms that differ only in their number of:Chlorine's listed atomic mass is 35.45, a non-whole number. What does this decimal reflect?The time required for half of a radioactive isotope's original concentration to decay to a more stable form isThe octet rule states that, with the exception of the innermost shell, atoms are most energetically stable wheWhen an atom gains electrons to become a negatively charged ion, its elemental name is altered to end in whichIn a water molecule, the electrons in the polar covalent O-H bonds are pulled more toward the oxygen atom. WhaA weak attraction between a slightly positive hydrogen atom (already covalently bonded to a highly electronegaA nonpolar covalent bond forms between two atoms that:Water's high heat capacity means it heats up and cools down slowly. About how many times greater is water's spThe amount of energy required to change one gram of a liquid substance into a gas is called its:The attraction between water molecules to each other, arising from hydrogen bonding, is called:Water climbing up a narrow tube against gravity is driven by adhesion -- the attraction between water moleculeThe pH scale is mathematically defined as:An acid is a substance that, when placed in solution, does what to the hydrogen ion concentration?Hydrochloric acid (HCl) is described as a strong acid because, in water, it:The buffer system that helps maintain a stable pH in human blood mainly involves carbonic acid, bicarbonate ioThe pH scale is an inverse logarithmic scale. What is its full range?A carbon atom, with an atomic number of six, typically forms how many covalent bonds in order to satisfy the oWeak attractions between molecules, caused by temporary and uneven electron distributions rather than by hydro