Answer the following question given this paragraph: Look at the scissors in Figure below . As you can see from the figure, scissors consist of two levers and two wedges. You apply force to the handle ends of the levers, and the output force is exerted by the blade ends of the levers. The fulcrum of both levers is where they are joined together. Notice that the fulcrum lies between the input and output points, so the levers are first-class levers. They change the direction of force. They may or may not also increase force, depending on the relative lengths of the handles and blades. The blades themselves are wedges, with a sharp cutting edge and a thicker dull edge. Q: Are scissors simple or compound machines? Choices: - lever - neither - simple - compound A:
compound
Answer the following question given this paragraph: Q: What is the study of the energy transformations that occur in a collection of matter? Choices: - fluctuations - geophysics - kinetics - thermodynamics A:
thermodynamics
Q: Answer the following question given this paragraph: Q: Systemic communication through the phloem helps integrate the functions of the whole what? Choices: - bird - animal - insect - plant A:
A: plant
Question: Answer the following question given this paragraph: In ordinary chemical reactions, the nucleus of each atom (and thus the identity of the element) remains unchanged. Electrons, however, can be added to atoms by transfer from other atoms, lost by transfer to other atoms, or shared with other atoms. The transfer and sharing of electrons among atoms govern the chemistry of the elements. During the formation of some compounds, atoms gain or lose electrons, and form electrically charged particles called ions (Figure 2.28). Q: When atoms gain or lose electrons, they can form electrically charged particles called what? Choices: - crystals - eons - toxins - ions A:
Answer: ions
*Question*
Answer the following question given this paragraph: Ceres ( Figure below ) is a rocky body that orbits the Sun. It could be an asteroid or a planet. Before 2006, Ceres was thought to be the largest asteroid. Is it an asteroid? Ceres is in the asteroid belt. But it is by far the largest object in the belt. Ceres has such high gravity that it is spherical. Q: What explains the spherical shape of ceres, once thought to be the largest asteroid? Choices: - orbital plane - space debris - low gravity - high gravity A:
**Answer**
high gravity
(Q).
Answer the following question given this paragraph: So far, we have discussed elements and compounds that are electrically neutral. They have the same number of electrons as protons, so the negative charges of the electrons is balanced by the positive charges of the protons. However, this is not always the case. Electrons can move from one atom to another; when they do, species with overall electric charges are formed. Such species are called ions. Species with overall positive charges are termed cations, while species with overall negative charges are called anions. Remember that ions are formed only when electrons move from one atom to another; a proton never moves from one atom to another. Compounds formed from positive and negative ions are called ionic compounds. Individual atoms can gain or lose electrons. When they do, they become monatomicions. When atoms gain or lose electrons, they usually gain or lose a characteristic number of electrons and so take on a characteristic overall charge. Table 3.6 "Monatomic Ions of Various Charges" lists some common ions in terms of how many electrons they lose (making cations) or gain (making anions). There are several things to notice about the ions in Table 3.6 "Monatomic Ions of Various Charges". First, each element that forms cations is a metal, except for one (hydrogen), while each element that forms anions is a nonmetal. This is actually one of the chemical properties of metals and nonmetals: metals tend to form cations, while nonmetals tend to form anions. Second, most atoms form ions of a single characteristic charge. When sodium atoms form ions, they always form a 1+ charge, never a 2+ or 3+ or even 1 charge. Thus, if you commit the information in Table 3.6 "Monatomic Ions of Various Charges"to memory, you will always know what charges most atoms form. (In Chapter 9 "Chemical Bonds", we will discuss why atoms form the charges they do. ) Table 3.6 Monatomic Ions of Various Charges H+ Na+ K+ Ions formed by losing a single electron. Q: Electrons can move from one atom to another; when they do, specimens called what, with overall electric charges, are formed? Choices: - atoms - molecules - cations - ions A:
(A).
ions