Q: What are chemical bonds between atoms of nonmetals that share valence electrons called? Read this paragraph and choose the correct option from the provided answers: Covalent bonds are chemical bonds between atoms of nonmetals that share valence electrons. In some covalent bonds, electrons are not shared equally between the two atoms. These are called polar covalent bonds. The Figure below shows the polar bonds in a water molecule (H 2 O). The oxygen atom attracts the shared electrons more strongly than the hydrogen atoms do because the nucleus of the oxygen atom has more positively charged protons. As a result, the oxygen atom becomes slightly negative in charge, and the hydrogen atoms become slightly positive in charge. For another example of polar bonds, see the video at this URL: http://www. youtube. com/watch?v=1lnjg81daBs. Choices: - electron bonds - ionic bonds - gravitational bonds - covalent bonds A:
covalent bonds

Q: The best thermal conductors are also the best conductors of what, which is also related to the density of free electrons in them? Read this paragraph and choose the correct option from the provided answers: Note that in Table 14.3, the best thermal conductorssilver, copper, gold, and aluminumare also the best electrical conductors, again related to the density of free electrons in them. Cooking utensils are typically made from good conductors. Choices: - light - pollution - sound - electricity A:
electricity

Q: What is venus covered in a thick layer of? Read this paragraph and choose the correct option from the provided answers: Viewed through a telescope, Venus looks smooth and featureless. The planet is covered by a thick layer of clouds. You can see the clouds in pictures of Venus ( Figure below ). Choices: - storms - fog - gases - clouds A:
clouds

Q: What does the triploid cell develop into during fertilization? Read this paragraph and choose the correct option from the provided answers: Double Fertilization After pollen is deposited on the stigma, it must germinate and grow through the style to reach the ovule. The microspores, or the pollen, contain two cells: the pollen tube cell and the generative cell. The pollen tube cell grows into a pollen tube through which the generative cell travels. The germination of the pollen tube requires water, oxygen, and certain chemical signals. As it travels through the style to reach the embryo sac, the pollen tube's growth is supported by the tissues of the style. In the meantime, if the generative cell has not already split into two cells, it now divides to form two sperm cells. The pollen tube is guided by the chemicals secreted by the synergids present in the embryo sac, and it enters the ovule sac through the micropyle. Of the two sperm cells, one sperm fertilizes the egg cell, forming a diploid zygote; the other sperm fuses with the two polar nuclei, forming a triploid cell that develops into the endosperm. Together, these two fertilization. Choices: - membrane - tubers - zygote - endosperm A:
endosperm