Answer: pure substances.
Explanation:
The given substances are:
All what surrounds us, which has mass and occupies spaces, is matter. There are two kind of matter: pure substances and mixtures.
Pure substances have a uniform and constant composition. On the other hand, mixtures are combinations of two or more pure substances in any arbitratry ratio.
Pure substances may be elements or compounds. The elements are the substances conmposed by one only kind of atom. In the list of substances given, Li and O₂ are elements: all the atoms in Li are lithium, and all the atoms in O₂ are oxygen atoms.
Compounds are the chemical combination of two or more different kind of atoms. In the given list H₂O₂ and NaCl are compounds. As you see, H₂O₂ contains atoms of hydrogen and oxygen, chemically bonded, in a fixed ratio (2 atoms of hydrogen by 2 atoms of oxygen). And NaCl has atoms of Na (sodium) and Cl (chlorine), chemicaly bonded, in a fixed ratio (1:1).
There are only 118 known elements and you can find them in any modern periodic table. Therer are virtually infinitely many compounds since many different combinations of the elements can be attained.
Elements and compounds have in common that they are classified as pure substances.
The answer is 3. The releasing of energy means exothermic reaction. So the ΔH should be negative. And the greatest quantity of energy released means that the greatest number. So according to the table I, the answer is 3.
Only one molecule have <u>sp2 </u>hybridization on central atom and that is <u>SO₂</u>.
<u>XeCl₂</u> have <u>sp3d </u>hybridization.
<u>OCl₂</u> have <u>sp3 </u>hybridization.
<u>HCN </u>have <u>sp </u>hybridization.
Hybridization is defined as the concept of mixing two atomic orbitals to give rise to a new type of hybridized orbitals.
Hybridization intermixing usually results in the formation of hybrid orbitals having entirely different energies, shapes, etc.
Learn more about hybridization here:- brainly.com/question/22765530
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Answer:
Sulphur
Explanation:
Sulphur(S) is the Sixteenth element of the periodic table and it has an electronic configuration of 2,8,6. This means it has six electrons in its outermost shell( valence electrons).
Sulphur has sixteen(16) protons which is equal to the atomic number which is also sixteen. Sulphur ends with the letter ‘r’. All the descriptions of the element are satisfied and it validates Sulphur.
