问题 问答题

在由铜锌组成的原电池(电解质是稀硫酸)中,有位同学在铜电极收集到了12g的气体,

(1)铜锌原电池的正、负极的电极反应:正极:______  负极:______

(2)铜电极产生12g气体的过程中有______g的锌溶解.

(3)铜电极产生12g气体的过程中有______mol的电子发生了转移.

答案

(1)在Cu、Zn和稀硫酸组成的原电池中,锌失电子变成离子进入溶液,发生氧化反应,是负极,电极反应式为Zn-2e-=Zn2+,正极上是氢离子得电子生成氢气,金属铜是正极,电极反应为:2H++2e-=H2↑,故答案为:2H++2e-=H2↑;Zn-2e-=Zn2+

(2)根据铜电极上的反应:2H++2e-=H2↑,产生2g气体的过程中有2mol的电子转移,所以产生12g气体的过程中有12mol电子转移,据Zn-2e-=Zn2+,则消耗金属锌的质量是:65g/mol×6mol=390g,故答案为:390;

(3)根据铜电极上的反应:2H++2e-=H2↑,产生2g气体的过程中有2mol的电子转移,所以产生12g气体的过程中有12mol电子转移,故答案为:12.

填空题
填空题

Motivation is "the driving force within individuals that impels them to action." And goals are the sought-after results (1) motivated behavior.
Motivation can be either positive or negative (2) direction. We may feel a driving force toward some object or condition, (3) a driving force away from some object or condition. For example, a person may be impelled toward a restaurant to fulfill a need, hunger, and away (4) an airplane to fulfill a need of safety. Some psychologists refer to positive drives (5) needs, wants or desires, (6) negative drives as fears or aversions. (7) , though negative and positive motivational forces seem to differ dramatically (8) terms of physical and sometimes emotional activity, they are basically similar in (9) they both serve to initiate and sustain human behavior. (10) this reason, researchers often refer (11) both kinds of drives or motives as needs, wants and desires.
Goals, (12) , can be either positive or negative. A positive goal is one toward (13) behavior is directed and it is often referred to as an approach object. A negative goal is (14) from which behavior is directed away and it is sometimes referred to as an avoidance object. Since both approach and avoidance goals can be considered objectives of motivated behavior, most researchers refer to (15) types simply as goals. Consider this example. A middle-aged woman may wish to remain (16) attractive as possible. Her positive goal is to appear desirable, and (17) she may use a perfume advertised to make her irresistible. A negative goal may be to prevent her skin (18) aging, and therefore she may buy and use face creams. (19) the former case, she uses perfume to help her achieve her positive goal -- attractiveness; in the (20) case, she uses face creams to help avoid a negative goal -- wrinkled skin.