Answer:
<h3>a. noble gases</h3>
Explanation:
Groups are numbered 1–18 from left to right. The elements in group 1 are known as the alkali metals; those in group 2 are the alkaline earth metals; those in 15 are the pnictogens; those in 16 are the chalcogens; those in 17 are the halogens; and those in 18 are the noble gases.
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The Earth's axis is responsible for making Earth tilt causing our seasons
Answer:
= 3/4
Explanation:
Half life is the time taken by a radioactove element to decay by half of its original mass.
The half life of tritium is 12.3 years , therefore it would take 12.3 years for tritium to decay to a half its original mass.
Using the formula;
New mass = Initial mass × (1/2)^n ; where n is the number of half lives.
n = 5.2 years/12.3 years
= 52/123
Therefore;
New mass = 1 × (1/2)^(52/123)
= 0.74599
= 0.75
The fraction of a tritium sample after 5.20 years will be approximately 3/4
How difficult it is to change an objects motion. Think of a tablecloth; it takes energy to move it from underneath objects on the table, and it takes energy to move the objects themselves on the table.
Reaction arrows are used to describe the state or progress of a reaction. 2.1 The Chemical Reaction Arrow. The chemical reaction arrow is one straight arrow pointing from reactant(s) to product(s) and by-products, sometimes along with side products. A → B. It is the most widely used arrow.
Boron is a chemical element with the symbol B and atomic number 5. Produced entirely by cosmic ray spallation and supernovae and not by stellar nucleosynthesis, it is a low-abundance element in the Solar System and in the Earth's crust
The C5 (C5) fraction is a co-product of naphtha cracking and is used as a raw material for synthetic rubber and petroleum resins.
Deuterium
Deuterium is frequently represented by the chemical symbol D. Since it is an isotope of hydrogen with mass number 2, it is also represented by 2. H. .
Unimolecular Elimination (E1) is a reaction in which the removal of an HX substituent results in the formation of a double bond. It is similar to a unimolecular nucleophilic substitution reaction (SN1) in various ways. One being the formation of a carbocation intermediate.
Aqueous (aq.): In the presence of water, often meaning water is the solvent. Aqueous NaCl. Anhydrous NaCl.
Hydrogen is the chemical element with the symbol H and atomic number 1. ... Since hydrogen readily forms covalent compounds with most nonmetallic elements, most of the hydrogen on Earth exists in molecular forms such as water or organic compounds.
Catalyst, in chemistry, any substance that increases the rate of a reaction without itself being consumed. Enzymes are naturally occurring catalysts responsible for many essential biochemical reactions.
Kp is the equilibrium constant calculated from the partial pressures of a reaction equation. It is used to express the relationship between product pressures and reactant pressures. It is a unitless number, although it relates the pressures.
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