Which of the following statements is not true regarding physical properties and changes?

a. physical changes include evaporating, boiling, and dissolving.
b. physical changes can change compounds into elements.
c. physical properties can be observed without any change in the substance's identity.
d. a series of physical changes, such as filtration and heating, can be used to separate substances with different physical properties.

Option (B) is the correct answer.

Explanation:

Physical properties and changes are defined as the property or changes that does not cause any change in the chemical composition of a substance.

For example, cutting a piece of sodium with knife is a physical change.

Whereas boiling point, density, melting point etc are all physical changes.

On the other hand, changes that bring change in chemical composition of a substance are known as chemical changes.

For example, reactivity, toxicity etc are all chemical changes.

Hence, we can conclude that the statement physical changes can change compounds into elements, is not true regarding physical properties and changes.

they emit helium gas that attaches to nearby planets.

they remove low-mass elements from the planets’ crust.

they cause nuclear fusion inside the inner core of planets.

they produce heavy elements such as iron and gold.

explanation:

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.