问题 填空题

在固体中,分子力作用较______,因而,固体有一定的______和______;在液体中,分子力作用较______,因而,液体没有确定的______,但占有一定的______;在气体中,分子力作用更______,因而,气体没有固定的形状,也没有确定的体积.

答案

固态物质中,分子排列十分紧密,分子间有强大的作用力.因而,固体具有一定的体积和形状.

液态物质中,分子没有固定的位置,运动比较自由,分子间的作用力比固体的小.因而,液体没有固定的形状,具有流动性,但有一定的体积.

气态物质中,分子极度散乱,间距很大,并能自由地向各个方向运动,分子间的作用力极小,容易被压缩.因此气体具有流动性,没有固定的形状也没有确定的体积.

故答案为:大;体积;形状;小;形状;体积;小.

填空题
填空题

For more than two centuries, American’s colleges and universities have been the backbone of the country’s progress. They have educated the technical, managerial, (1) and provided generation after generation of national leaders. Today educators from around the globe are turning to U. S. institutions of higher learning (2) . They are apt to find many reasons for the excellence of American universities, but (3) stand out as watersheds:
Education (4) : In 1862 Congress enacted the Land-Grant College Act, which essentially extended the opportunity of higher education (5) , including such disenfranchised groups as women and minorities. Each state was permitted to sell large tracts of (6) and use the proceeds to endow at least one public college.
(7) : Over the years, the decentralization and diversity of the America’s colleges and universities have promoted competition for students and resources. Competitive pressure first arose (8) . The academy’s impact really grew after World War II, when (9) commissioned by President Roosevelt argued that it was the federal government’s responsibility to (10) for basic research. Instead of being centralized in government laboratories, scientific research (11) in American universities and generated increasing investment. It also gave graduate students research opportunities and helped (12) far and wide, to the benefit of industry, medicine and society as a whole.
(13) : The end of the World War II saw passage of the Servicemen’s Readjustment Act of 1944. The law, which provided for (14) for returning veterans, made an already democratic higher-education system accessible in ways that were (15) in Europe, opening the doors of the best universities to men and women who had (16) of going to college.
(17) : The creation of federal loan guarantees and subsidy programs, as well as outright grants for college students brought (18) to higher education and further helped to democratize access. Since its founding (19) , the Federal Family Education Loan Program has funded more than 74 million student loans worth more than (20) .