Chemistry - Study Mode

[#226] Which of the following is the maximum number of electrons that can be present in M-shell?
Correct Answer

(C) 18

Explanation

Solution: The M shell only holds eight electrons. The M shell can actually hold up to 18 electrons as you move to higher atomic numbers. The maximum number of electrons you will find in any shell is 32.

[#227] Atoms of different elements have
Correct Answer

(C) Different atomic number and different number of valence electrons

Explanation

Solution: The atoms of different elements have different numbers of electrons, protons, and neutrons. Every element is unique and has an atomic number. That number tells you the number of protons in every atom of the element. The atomic number is also called the proton number.

[#228] Which of the following phenomenon is considered responsible for Global Warming?
Correct Answer

(A) Greenhouse effect

Explanation

Solution: The Greenhouse effect is the main thing that causes global warming. It's like a blanket around the Earth. Certain gases in the atmosphere (like carbon dioxide) trap heat from the sun. Normally, some of this heat would escape back into space. But, when we burn too much fuel (like coal, oil, and gas), we release more of these gases. This makes the "blanket" thicker, trapping more heat and warming the planet. Let's look at why the other options are wrong: B) Fire in coal mines: While coal mine fires are bad for the environment, they don't cause global warming directly on a global scale like the greenhouse effect. C) Dry farming: Dry farming is a method of farming in dry areas. It can have environmental impacts, but it's not a direct cause of global warming . D) Monsoon: Monsoon are seasonal winds and rain. They are part of the Earth's climate system, but they don't cause global warming itself. In fact, climate change and global warming can affect monsoon patterns . E) Trade winds: Trade winds are constant winds in the tropics. Like monsoon, they are part of Earth's climate, not a cause of global warming . So, the greenhouse effect is the most important thing to understand when talking about global warming !

[#229] The nucleus of an atom consists of
Correct Answer

(C) protons and neutrons
(E) Protons and Neutrons

Explanation

Solution: The nucleus of an atom consists of protons and neutrons.

[#230] The number of moles of solute present in 1 kg of a solvent is called its
Correct Answer

(A) molality

Explanation

Solution: Molality is the property of a a solution that is defined as the number of moles of solute per kilogram of solvent.