Explanation

• Methyl orange is a pH indicator that changes color in response to changes in acidity or basicity.
• In an acidic medium, it is orange (or red), and in a basic medium, it turns yellow.

Explanation

• Lead-210 is used to determine the accumulation rates of pollutants in layers of soil.
• It helps in studying sedimentation rates and the historical deposition of pollutants.

Explanation

The molecule that exhibits all three types of bonding—ionic, covalent, and coordinate covalent—is NH4Cl (ammonium chloride).

Ionic Bonding:

In NH4Cl, the bond between ammonium (NH4+) and chloride (Cl-) ions is primarily ionic.

Covalent Bonding:

Within the ammonium ion (NH4+), the bonds between nitrogen and hydrogen atoms are covalent.

Coordinate Covalent Bonding:

In NH4Cl, there is also a coordinate covalent bond between the ammonia (NH3) molecule and a proton (H+) from hydrochloric acid (HCl) that forms ammonium (NH4+)

Explanation

• Dilution refers to the process of decreasing the concentration of a solution by adding more solvent.
• While ionisation involves the formation of ions from molecules in a solution.

Explanation

• Air is essentially transparent.
• It allows all light to pass through it without scattering or absorbing any of the light.

Explanation

• Fog is a type of cloud that forms at ground level.
• It characterized by a thick cloud of water droplets suspended in the air near the Earth's surface.
• This reduces visibility and creates a misty or foggy condition.

Explanation

• The temperature range of the clinical thermometer is 94°F to 108°F.
• A clinical thermometer is a device that measures the temperature of the body.
• A mercury bulb is located at the end of a long, narrow glass tube.
• The average body temperature is 37° C, but it can range between 35 and 42° C.

Explanation

• James Prescott Joule established that the various forms of energy, mechanical, electrical and heat, are basically the same and can be changed from one form into another.
• He demonstrated that different forms of energy are interchangeable in his most famous experiment, published in 1845, using a paddle wheel to show that mechanical energy could be changed into thermal energy.

Explanation

• Temperature is the measurement of the hotness or coldness of an object or substance.
• It is a physical property that is usually measured in units of Celsius (°C), Fahrenheit (°F), or Kelvin (K).

Explanation

• A gas is a state of matter that has neither a fixed shape nor a fixed volume.
• It expands to fill its container and takes the shape of its container.
• Gases are highly compressible and can change shape and volume easily.
• Liquid: A liquid has a fixed volume but not a fixed shape.
• Solid: A solid has both a fixed shape and a fixed volume.