Answer the following question given this paragraph: The color of a material is due to the ability of its atoms to absorb certain wavelengths while reflecting or reemitting others. A simple red material, for example a tomato, absorbs all visible wavelengths except red. This is because the atoms of its hydrocarbon pigment (lycopene) have levels separated by a variety of energies corresponding to all visible photon energies except red. Air is another interesting example. It is transparent to visible light, because there are few energy levels that visible photons can excite in air molecules and atoms. Visible light, thus, cannot be absorbed. Furthermore, visible light is only weakly scattered by air, because visible wavelengths are so much greater than the sizes of the air molecules and atoms. Light must pass through kilometers of air to scatter enough to cause red sunsets and blue skies. Q: What weakly scatters visible light? Choices: - space - Reflection - water - air A:
air
(Question)
Answer the following question given this paragraph: All matter is composed of tiny indivisible particles called atoms. All atoms of an element are identical in mass and chemical properties, whereas atoms of different elements differ in mass and fundamental chemical properties. A chemical compound is a substance that always contains the same atoms in the same ratio. In chemical reactions, atoms from one or more compounds or elements redistribute or rearrange in relation to other atoms to form one or more new compounds. Atoms themselves do not undergo a change of identity in chemical reactions. This last hypothesis suggested that the alchemists' goal of transmuting other elements to gold was impossible, at least through chemical reactions. We now know that Dalton's atomic theory is essentially correct, with four minor modifications:. Q: All matter is composed of tiny indivisible particles called atoms. all atoms of an element are identical in mass and this? Choices: - acid properties - liquid properties - electrical properties - chemical properties A:
(Answer)
chemical properties
Ques: Answer the following question given this paragraph: The classes of elements are metals, metalloids, and nonmetals. They are color-coded in the table. Blue stands for metals, orange for metalloids, and green for nonmetals. You can read about each of these three classes of elements later in the chapter, in the lesson "Classes of Elements. ". Q: Metals, metalloids, and nonmetals are the different classes of what? Choices: - compounds - structures - ions - elements A:
Ans: elements
(Q).
Answer the following question given this paragraph: Summary 3.1 Formula Mass and the Mole Concept The formula mass of a substance is the sum of the average atomic masses of each atom represented in the chemical formula and is expressed in atomic mass units. The formula mass of a covalent compound is also called the molecular mass. A convenient amount unit for expressing very large numbers of atoms or molecules is the mole. Experimental measurements have determined the number of entities composing 1 mole of substance to be 6.022 1023, a quantity called Avogadro's number. The mass in grams of 1 mole of substance is its molar mass. Due to the use of the same reference substance in defining the atomic mass unit and the mole, the formula mass (amu) and molar mass (g/mol) for any substance are numerically equivalent (for example, one H2O molecule weighs approximately18 amu and 1 mole of H2O molecules weighs approximately 18 g). 3.2 Determining Empirical and Molecular Formulas The chemical identity of a substance is defined by the types and relative numbers of atoms composing its fundamental entities (molecules in the case of covalent compounds, ions in the case of ionic compounds). A compound's percent composition provides the mass percentage of each element in the compound, and it is often experimentally determined and used to derive the compound's empirical formula. The empirical formula mass of a covalent compound may be compared to the compound's molecular or molar mass to derive a molecular formula. 3.3 Molarity Solutions are homogeneous mixtures. Many solutions contain one component, called the solvent, in which other components, called solutes, are dissolved. An aqueous solution is one for which the solvent is water. The concentration of a solution is a measure of the relative amount of solute in a given amount of solution. Concentrations may be measured using various units, with one very useful unit being molarity, defined as the number of moles of solute per liter of solution. The solute concentration of a solution may be decreased by adding solvent, a... Q: The formula mass of a covalent compound is also called the what? Choices: - atomic mass - ionic mass - nucleus mass - molecular mass A:
(A).
molecular mass
Ques:Answer the following question given this paragraph: Animals and most plants have two special chromosomes. They are called sex chromosomes . These are chromosomes that determine the sex of the organism. All of the other chromosomes are called autosomes . Genes on sex chromosomes may be inherited differently than genes on autosomes. Q: What term describes all but the sex chromosomes? Choices: - lysosomes - telomeres - sporozoans - autsomes A:

Ans:autsomes
Answer the following question given this paragraph: Q: What is the capacity to cause change? Choices: - gravity - temperature - mass - energy A:
energy