Which of the following is not a state of matter?
The question asks to identify which option is NOT a state of matter. We need to recall the fundamental states of matter and compare them with the given options.
Correct Option: D) Energy is not a state of matter. It is a fundamental physical quantity that describes the capacity to do work or produce heat, distinct from matter which has mass and occupies space.
The question asks to identify the process where a solid directly converts into a vapor without passing through the liquid state. This is a fundamental concept in the states of matter and their phase transitions.
C) Sublimation is the process where a solid changes directly into a gas (vapor) without first becoming a liquid. This is precisely what the question describes.
The question asks to identify the specific point on a phase diagram where all three common phases of matter (solid, liquid, and gas) can coexist in thermodynamic equilibrium. This requires understanding the definitions of key points on a typical phase diagram.
Correct Option: B) Triple point is the specific temperature and pressure at which the solid, liquid, and gaseous phases of a substance coexist in thermodynamic equilibrium.
The question asks about the relationship between the density of a gas and its pressure. We need to recall the definition of density and how pressure affects the volume of a gas, keeping in mind that the mass of the gas remains constant.
A) Increases — As pressure on a gas increases (at constant temperature), its volume decreases. Since density is mass divided by volume, and the mass remains constant, a decrease in volume leads to an increase in density.
This question tests fundamental knowledge about the properties of gases, specifically the nature of intermolecular forces. Understanding the kinetic molecular theory of gases is key to answering this question.
C) Non-existent — In an ideal gas model, the attractive forces between molecules are considered to be non-existent. In real gases, these forces exist but are very weak and become significant only at high pressures and low temperatures where molecules are closer together.
The question asks for the boiling point of water in the Fahrenheit scale. This is a fundamental concept in temperature scales and requires knowledge of the standard reference points for water.
D) 212°F is the correct boiling point of water on the Fahrenheit scale at standard atmospheric pressure.