The elements that do not ordinarily form compounds are noble gases as they have complete octet.
An element is defined as a substance which cannot be broken down further into any other substance. Each element is made up of its own type of atom. Due to this reason all elements are different from one another.
Elements can be classified as metals and non-metals. Metals are shiny and conduct electricity and are all solids at room temperature except mercury. Non-metals do not conduct electricity and are mostly gases at room temperature except carbon and sulfur.
The number of protons in the nucleus is the defining property of an element and is related to the atomic number of the element.All atoms with same atomic number are atoms of same element.
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Answer: Option (b) is the correct answer.
Explanation:
Elements which belong to same group show similar chemical properties.
This is because elements which are present in the same group have same number of valence electrons. Hence, they tend to show same type of reactivity which makes them exhibit similar chemical properties.
As chemical properties are defined as the properties which tend to show difference in chemical composition of a substance.
For example, toxicity, reactivity, combustion etc are all chemical properties.
Here, oxygen and sulfur are both group 16 elements. So, they tend to show similar chemical properties.
Thus, we can conclude that oxygen and sulfur elements have the most similar chemical properties.
Among the given pairs, oxygen and sulfur display the most similar chemical properties because they are in the same group of the periodic table (Group 16, or the chalcogens), and thus have the same number of valence electrons (six), leading to similar chemical reactivity.
Among the pairs of elements presented in the original question (boron and carbon, oxygen and sulfur, aluminum and bromine, argon, and silicon), the pair that has the most similar chemical properties is oxygen and sulfur. This is due to their placement within the same group on the periodic table, specifically the chalcogens, or Group 16.
Elements in the same group of the periodic table typically exhibit similar chemical properties because they have the same number of valence electrons. For example, boron and carbon, although neighbors on the periodic table, do not exhibit highly similar chemical properties due to their different numbers of valence electrons.
On the other hand, oxygen and sulfur, both being members of Group 16, have six valence electrons and thus exhibit similar chemical reactivity and form similar types of compounds, despite their differences in physical properties.
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Ar
F
Fr
S
Answer:
An SN2 (substitution nucleophilic bimolecular) reaction
Explanation:
This is a type of organic reaction that involves a nucleophile attacking an electrophilic center, resulting in the displacement of a leaving group from that center. This type of reaction typically occurs at a saturated carbon atom, where the nucleophile displaces a leaving group attached to that carbon atom. The reaction is bimolecular because it involves the collision of two molecules, the nucleophile and the substrate.
b. conduction
c. cold air rising and warm air sinking
d. radiation
Answer:
cold air rising and warm air sinking
Explanation:
Convection is well known in nature. During convection, warm particles rise above the surface while cooler particles sink below. Hence a convection current is set up.
Air moves by convection. Hot air rises and moves toward and is then replaced with cooler air. A typical application of convection in nature is land and sea breeze.
Answer: +4
Explanation:
Firstly, we know that Oxygen should have an oxidation number of -2. This is because according to oxidation rules, Oxygen's number will always be -2 unless it is a part of a peroxide and then it will be -1 (ex: H2O2). UO2 is not a peroxide, so the regular rules will apply.
We also know that oxidation numbers in a molecule with no charge should add up to zero. There are two oxygen molecules which makes their total oxidation numbers equal to -4. Therefore, whatever U's oxidation number is should cancel out that -4 to make the total number 0.
So, U's oxidation number should be +4 since -4+4=0.