Answer:b.CaCl2
Explanation:
A compound is a substance resulting when two or more elements are are chemically bonded together either ionically or covalently in a fixed ratio.
From the given options we can see that the only compound there is CaCl2 which is an ionic compound in the fixed ratio of one calcium ion to two chloride ions.
Other options , Cu,Na and Nd are merely pure substance---Elements
Answer:
It’s true ( pure).
Explanation:
An element is defined as a pure substance that is not chemically combined with any other elements. An element comprises of mainly the sane type of atoms.
While a compound is a substance that consists of two or more elements which are chemically combined together. This is the main difference between an element and a compound.
Answer:
Compounds between Nonmetals and Nonmetals
Compounds that consist of a nonmetal bonded to a nonmetal are commonly known as Molecular Compounds, where the element with the positive oxidation state is written first. In many cases, nonmetals form more than one binary compound, so prefixes are used to distinguish them.
Answer:
Explanation:
a )
1.25 g MgO contains .754 g of Mg .Rest will be O
so oxide = 1.25 - .754 = 0.496 g
ratio of magnesium to oxide = .754/.496 = 1.52
b) 1.25 g of MgO contains .754 g of Mg
534 g of MgO contains .754 x 534 / 1.25 g = 322.11 g
