Answer:
its B
Explanation:
Because its can only go cold to hot. -hope this help :)
I only got 50 points (which is not 100). :-)
Look at the graph. At 80 °C, about 38 g of solute is able to dissolve, and that’s for ever 100 g of water. That means that for every 150 grams of water, 57 grams of solute can dissolve (38/2 = 19 + 38 = 57 g) at 80 °C. Since 57 g is greater than 55 g, all for he sodium chloride should dissolve in 150 g of water at 80 °C - you can put all of that into a “mathematical explanation”.
It is d. compounds because they have more than one element.
Answer:
Explanation:
Of course you could do the separation chemically. Dissolve the salt up in water, pass thru a filter, wash the iron filings with ethanol, which would encourage the salt to precipitate from solution.
I do hope I helped you! :)
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.
