Explanation

Elements can be classified as metals, metalloids, and nonmetals.

Explanation

Copper is a chemical element with symbol Cu and atomic number 29.

Classified as a transition metal, Copper is a solid at room temperature.

Explanation

 non-magnetic materials are examples

• Rubber
• plastic
• stainless steel
• feather
• paper
• mica
• gold
• Silver
• leather***

  ND18-1-2023

Explanation

Matter is a substance made up of various types of particles that occupy physical space and have inertia

Following are the basic three states of matter:

1. Solid
2. Liquid
3. Gas

ND4-4-20234

Explanation

Joseph Priestly discovered oxygen on August 1, 1774.

The most abundant element in the Earth's crust is oxygen, making up 46.6% of Earth's mass

Explanation

Good conductors of electricity:-

gold,

silver,

copper,

aluminum,

and graphite.

***

Bad conductors of electricity:-

plastic,

rubber,

glass,

air,

wood,

charcoal,

and diamond.

Explanation

Metallic bonds are the force of attraction between positive metal ions and valence electrons that are constantly moving around them.

Metallic bonds occur among metal atoms.

Whereas ionic bonds join metals to non-metals,

metallic bonding joins a bulk of metal atoms.

A sheet of aluminum foil and a copper wire are both places where you can see metallic bonding in action.

ND-21-5-2023

Explanation

The third edition of the popular Structural and Stress Analysis provides the reader with a comprehensive introduction to all types of structural and stress analysis.

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Explanation

Answer: 

C: Heating of Mercuric oxide powder: The heating of Mercuric oxide powder is a permanent change. We cannot get powder by revere reaction so it is a chemical change

Sublimation of Iodine: It is a physical change

Heating a platinum wire in a Bunsen flame: Platinum is a noble gas that cannot change its physical appearance after heating. So it is not a chemical change

Evaporation of Alcohol: It is a physical change. The liquid is changed into gas 

Explanation

Desalination – is a process by which saline water (generally sea water) is converted to fresh water.

The most common desalination processes are distillation and reverse osmosis.