Why is soft iron used as the core of the electromagnet in an electric bell? How do metals differ from nonmetals with regard to (a) number of valence electrons, (b) conductivity of heat and electricity, and (c) phase? How do metallic character change (a) across a period and (b ...
Why is californium so soft? Why are heavy metals toxic? Why are transition metals colored? Why is graphene important? Why do ionic compounds dissolve in water? Why do ionic compounds dissolve readily in water? Why is graphene used in bulletproof vests?
However, some metals are toxic to the human body.Heavy metalsare a group of relatively high-density metals that are toxic even at low concentrations. Elements like arsenic (As), mercury (Hg), lead (Pb), chromium (Cr) and cadmium (Cd) are considered heavy metals....
his metals the Dog slept; but when, on the other hand, he went todinner and began to eat, the Dog woke up and wagged his tail, asif he would ask for a share of his meal. His master one day,pretending to be angry and shaking his stick at him, said, "Youwretched little sluggard...
Unit 2 Lesson 8 Why Are Plants Important?练习 一、单项选择。 1. —What can you see ___ the tree? —Aha! Koalas! Seven of them! A. onB. in C. aboveD. over 2. Thanks to our teachers. ___ their help,...
Metals and other materials have different magnetic phases, depending on the temperature of the environment in which they are located. As a result, a metal may exhibit more than one form of magnetism. Iron, for example, loses its magnetism, becoming paramagnetic, whenheated above 1418°F(770°...
The metalslead and tinare both malleable and ductile ,biit their ' malleability, or spreading-out property, is much greater than ! Are alkali metals soft or hard? The alkali metals are solids at room temperature (except for hydrogen), but have fairly low melting points: lithium melts at 18...
There are dozens of ideas used to explain homosexual behaviour in insects, which broadly fall into two categories. Either they suggest insect homosexuality has evolved because it actually helps males have more offspring, or that it is not an evolutionary adaptation and instead occurs when males simp...
Chemically speaking, gold is a transition metal. Transition metals are unique,because they can bond with other elements using not just their outermost shell of electrons(the negatively charged particles that whirl around the nucleus), but also the outermost two shells. ...
Why are molecules with double bonds stronger than those with single bonds? Are triple bonds even stronger than double bonds?Answer and Explanation: Hi this is a great question! The double bonds are strong than single bonds because there are more...