Stoichiometry:
First, calculate the number of grams for one mole of Ca3 (PO3)4
(3 * (Mass of Ca)) + (4 * (Mass of P + (3 * Mass of Oxygen)))
= (3*40.08) + 4(30.97 + (3*16.00))
=(120.24) + 4(78.97)
=436.12 g / mol Ca3(PO3)4
This means there are 436.12 g per 1 mole of Ca(PO3)4. Since there are 4.50 moles of Calcium Phosphate, mulitply the molar mass of Ca(PO3)4 by 4.50 and you should get 1962.54 g. Since there are 3 sigfigs, the final answer is 1960 g.
on a side note: I put in all my work in case 1. your periodic table if different, 2. my work is wrong, 3. you put in the question wrong because I feel that the actual compound would be Ca3(PO4)3 instead of Ca3(PO3)4 (if this is the case, the answer should be 1820 g).
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.
Answer would be B. CNS the central nervous system
Answer:
elements on the left-hand side of the periodic table such as sodium and magnesium prefer to lose electrons to form a cation because this requires less energy to obtain a stable octet, and vice-versa for the right-hand side of the periodic table e.g. fluorine. However, using this reasoning I am not sure why all transition metals tend to lose electrons rather than gain them.
There is no graph but the reason people who have aids cant fight it off is because it is an immune disease it quickly weakens the immune system and makes a persons body too weak to fight anything off.