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 earth has the moon captured in its gravity. this keeps the moon in an elliptical orbit
Answer:
If the cap is left off, some of the dissolved CO2 can escape as gas from the bottle, making the pop go flat faster (less dissolved CO2 in pop). If the cap is placed tightly, the gaseous CO2 cannot readily escape the bottle thus your pop won't go flat
Explanation:
If the cap is left off, some of the dissolved CO2 can escape as gas from the bottle, making the pop go flat faster. If the cap is placed tightly, the gaseous CO2 cannot readily escape the bottle thus your pop won't go flat.
Just some fun related concept:
A similar concept comes into play for the reason behind why pop tastes better in fridge then just keeping at normal temperature. This is because gases tend to have high solubility at cold temperatures thus CO2 is more readily dissolved in fridge than outside room temperature which is why it tastes great!
Answer: Mass of 
produced in this reaction was 6.56 grams
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
Mass or reactants = Mass of 
+ mass of 
= 16.00 + 64.80 = 80.80 g
Mass of products = mass of aqueous solution + mass of + = 74.24 + x g
Mass or reactants = Mass of products
80.80 g = 74.24 + x g
x = 6.56 g
Thus mass of produced in this reaction was 6.56 grams
Answer:
The number of moles = 0.06 moles
Explanation:
i) Formula
Number of moles = Mass of the sample ÷ Molar masses of the substances
ii) Number of moles = 10.0 ÷ (137)+(19×2)
= 10.0 ÷ 175
= 0.06 moles
