Atoms are the smallest part of an element that retains its chemical properties. The element carbon is made up of carbon atoms. If you break up an atom of carbon, it isn’t carbon anymore. When two or more elements combine to form a new substance, it is called
a compound
.
What are two elements combined called?
Elements can be chemically combined into
compounds
, therefore, a compound consists of two or more elements combined, in definite proportions, by chemical means. Compounds may be formed by combining atoms of their constituent elements by ionic bonds or by covalent bonds.
What can elements combine to form?
When two distinct elements are chemically combined—i.e., chemical bonds form between their atoms—the result is called a
chemical compound
. Most elements on Earth bond with other elements to form chemical compounds, such as sodium (Na) and Chloride (Cl), which combine to form table salt (NaCl).
Which of the following is the most reactive most likely to combine with another element )?
All halogens
are electronegative: they gain electrons very quickly, making them the most reactive of all chemical elements. Halogens easily dissociate into atomic particles and can combine with surrounding elements to form compounds. Halogens are generally poisonous; each has a different level of toxicity.
Which elements are least likely to combine with other elements?
- Noble Gases are colorless gases that are extremely un-reactive.
- Because they do not readily combine with other elements to form compounds, the noble gases are called inert.
- The family of noble gases includes helium, neon, argon, krypton, xenon, and radon.
What is form when two or more materials are combined?
When two or more elements combine to form a new substance, it is called
a compound
. There are many different types of compounds, because atoms of elements combine in many different ways to form different compounds. Examples include water (H
2
O) and table salt (NaCl).
What is form when two or more substance are combined?
A chemical reaction
occurs when two or more substances are combined to form a new substance and cannot be separated back into its original substances.
What do we get when two or more elements are combined Class 9?
A compound
is a substance formed when two or more chemical elements are chemically bonded together. … In chemistry a mixture is a material made up of two or more different substances which are physically combined.
What are the two elements of proportion?
In chemistry, the law of multiple proportions states that if two elements form more than one compound, then the ratios of
the masses of the second element
which combine with a fixed mass of the first element will always be ratios of small whole numbers.
Which element in group 1 is the least reactive?
Reactivity of Group 1 Elements
The reactivity of alkali metals increases from the top to the bottom of the group, so
lithium (Li)
is the least reactive alkali metal and francium (Fr) is the most reactive.
Which element in group 2 reacts the most vigorously?
The alkaline earth metals (Be, Mg, Ca, Sr, Ba, and Ra) are the second most reactive metals in the periodic table, and, like the Group 1 metals, have increasing reactivity in the higher periods.
Beryllium (Be)
is the only alkaline earth metal that does not react with water or steam, even if metal is heated to red heat.
What is the least reactive element in group 2?
The least reactive element in group 2 is
beryllium
. Even at red heat beryllium will not react with water and it does not react with dinitrogen (N
2
).
What three elements make up 99%?
The human body is approximately 99% comprised of just six elements:
Oxygen, hydrogen, nitrogen, carbon, calcium, and phosphorus
. Another five elements make up about 0.85% of the remaining mass: sulfur, potassium, sodium, chlorine, and magnesium.
What is the first element in Group 13?
Group 13 is sometimes referred to as the
boron group
, named for the first element in the family. These elements are–not surprisingly–located in column 13 of the periodic table. This group includes boron, aluminum, gallium, indium, thallium, and ununtrium (B, Al, Ga, In, Tl, and Uut, respectively).
How many elements are in the transition metals?
Most scientists simply regard the transition metals as the elements in the d-block (groups 3-12) on the periodic table. There are total of
38 elements
in this group including Cobalt, Nickel, Iron, Rhodium, Gold, Silver, Cooper, Scandium, Titanium, Vanadium, Manganese, Zinc and Mercury.
