He isn’t good at science. He has no idea ___ an atom is.A. whoB. whichC. whatD. that 相关知识点: 试题来源: 解析 C 题目考查疑问代词在宾语从句中的用法。原句需要表达“他不知道原子是什么”,宾语从句“___ an atom is”需要带有疑问意义的引导词。**选项分析:**1. **A. who**:...
How is the nitrogen-15 isotope different from the nitrogen-14 atom? What does suitable control mean in an experiment to investigate the effects of different light intensities on rate of photosynthesis? How to identify the control group? The experimental group?
Science is a social process in which the community's scrutiny(监视) ensures we have the best available knowledge. "Best available" does not mean "definitive", but the best we have until we find out how to improve it.The long history of evolution(量子) shows how science is a process ...
What does the atomic symbol represent? Chemical Element: A chemical element is defined as a particular type of atom, which can be identified by the amount of protons the element holds in its nucleus. The number of protons in the nucleus of the atom is what gives the element different traits...
What does the nucleus do? The nucleus was discovered in 1911 by Ernest Rutherford, a physicist from New Zealand, according to theAmerican Institute of Physics. In 1920, Rutherford proposed the name proton for the positively charged particles of the atom. He also theorized that there was a neut...
All matter consists of atoms, which, in turn, consist of protons, neutrons and electrons. Both protons and neutrons are located in the nucleus, which is at the center of an atom. Protons are positively charged particles, while neutrons are neutrally charged. Electrons are negatively charged, ...
According to string theory, all the elementary particles in the universe are vibrating, one-dimensional filaments of energy known as strings. Strings have no width or height, but they do have length, which is estimated to be 10-35meters -- many times smaller than the diameter of an atom's...
By small, I really do mean absolutely, nanoscopically tiny: a single atom is hundreds of thousands of times thinner than a human hair, so you have absolutely no chance of ever seeing one unless you have an incredibly powerful electron microscope. In ancient times, people thought atoms were ...
(e.g., Watson and Crick’s metal model of DNA, or the fruit fly and other model organisms in biology), but most of them are abstract/mathematical objects (e.g., Bohr’s model of the atom, the Lotka-Volterra model of predator-prey interaction, the Newtonian model of the solar system...
Another way to look at what an atom example is is to see examples of things that arenotatoms. Atoms are units of matter, so by definition, anything that does not consist of matter is not an atom. Light, heat, dreams, and sound are not atoms. ...