Skip to content Home Questions Play Progress Daily Challenge Questions › Chemistry Questions QUESTION Which of the following chemical reactions takes place when quicklime reacts with water? Open question → QUESTION For the reaction 4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g), which statements are true? (i) Nitrogen is oxidised. (ii) Oxygen is oxidised. (iii) Nitrogen… Open question → QUESTION Which listed gas produces the characteristic orange-red glow in a low-pressure electrical discharge? Open question → QUESTION In the electron-transfer description of a redox reaction between a reducing agent and an oxidising agent, which listed process occurs? Open question → QUESTION Who, in the 1860s, undertook a thorough investigation of the gas laws expressing the relationships of pressure, temperature and volume in carbon dioxide? Open question → QUESTION Which is the approximate value of the Avogadro constant, in mol⁻¹? Open question → QUESTION One mole of an ideal gas occupies a volume of ______ litre at 273 K and 1 atm pressure. Open question → QUESTION For an ideal mixture of non-reacting gases, which law states that total pressure equals the sum of the component partial pressures? Open question → QUESTION Consider the following statements: 1. Ignition temperature is the lowest temperature at which a substance catches fire. 2. Kerosene has a high ignition temperature… Open question → QUESTION Who reported in 1662 that, for a fixed amount of gas at constant temperature, decreasing its volume increases its pressure? Open question → QUESTION Consider the following statements about the properties of an ideal gas: 1. The volume of ideal gas molecules is negligible compared to the total… Open question → QUESTION Which specific environmental condition found in waterlogged soils of rice paddies and wetlands directly facilitates the significant microbial production of methane a potent greenhouse… Open question → QUESTION Which radioactive element has atomic number 43 and no stable isotopes? Open question → QUESTION Which chemical element of Group 18 of the periodic table is produced by the natural radioactive decay of uranium in soils and rocks? Open question → QUESTION Which of the following elements is a member of the actinide series? Open question → QUESTION At 20 °C and approximately 1 atm pressure, how many of the familiar elements are gases? Open question → QUESTION Consider the following statements about the familiar Group 6 metals chromium, molybdenum and tungsten. 1. Chromium is a Group 6 element with variable oxidation… Open question → QUESTION Which element has a symbol derived from hydrargyrum, a Latinised Greek name meaning liquid silver? Open question → QUESTION Identify the group of the periodic table to which cobalt belongs. Open question → QUESTION What is the atomic number of nobelium, the element named after Alfred Nobel? Open question → QUESTION First produced in 1955, which element number belongs to mendelevium, named in honour of Dmitri Mendeleev? Open question → QUESTION Who conducted X-ray spectroscopic study of a large number of elements and showed that the frequency of X-rays emitted by an element is related… Open question → QUESTION Which Group 13 soft metal melts near 303 K and is important in semiconductor and solid-state device technology? Open question → QUESTION Hydrogen resembles the properties of which two groups of the periodic table? Open question → Home Questions Play Progress 