All elements are made up of atoms. ➢ Atoms are made up of protons, neutrons, and electrons. Two different kinds of atoms can combine to form a compound. A molecule is a combination of atoms that cannot be broken apart while still retaining the same properties as the larger substance that it is a part of.
The primary greenhouse gases are water vapor, carbon dioxide, methane, nitrous oxide, and ozone. So, the correct answer among these options is water vapor, that is considered to be a greenhouse gas.
Answer : Broadly solids are divided into three categories;
i) Crystalline solids have a regular definite structure, in which the particles pack in a repeating pattern from one edge of the solid to the other.
ii) Amorphous solids have a random structure, with little unorganized pattern long-range order.
iii) Polycrystalline solids are those where an aggregate which consists of a large number of small crystals or grains in which the structure is regular, but the crystals or grains are found to be arranged in a random fashion.
Also solids can be divided into 3 more categories according to their bonds;
i) Covalent solids, like diamond, which forms crystals that can be viewed as a single giant molecule made up of an almost endless number of covalent bonds.
ii) Ionic solids are basically salts, such as NaCl, in which the molecules are held together by the strong force of attraction between ions of opposite charge.
iii) Metallic solids are found in metals which have the force of attraction between atoms of metals, such as copper and aluminum, or alloys, such as brass and bronze, are metallic bonds.
Answer:
62.5 moles of O₂.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
2C₈H₁₈ + 25O₂ —> 16CO₂ + 18H₂O
From the balanced equation above,
2 moles of C₈H₁₈ reacted with 25 moles of O₂.
Finally, we shall determine the number of mole of O₂ needed to react with 5 moles of C₈H₁₈. This can be obtained as shown below:
From the balanced equation above,
2 moles of C₈H₁₈ reacted with 25 moles of O₂.
Therefore, 5 moles of C₈H₁₈ will react with = (5 × 25) / 2 = 62.5 moles of O₂.
Thus, 62.5 moles of O₂ is needed for the reaction.
207.217 amu
Work:
203.973 amu *(0.014) = 2.855 amu
205.974 amu *(0.241) = 49.639 amu
206.976 amu *(0.221) = 45.741 amu
207.977 amu *(0.524) = 108.979 amu
2.855 + 49.639 + 45.741 + 108.979 = 207.217 amu
