A. The balance was not calibrated properly. B. The color of the substance was bright. C. The laboratory was too cold. D. The students were in a hurry. 相关知识点: 试题来源: 解析 A。解析:测量物质质量不一致可能是因为天平没有正确校准,A 选项正确。B 选项物质颜色亮不会影响质量测量。C 选...
■ One mole of a substance is the amount of substance that has the same number of particles as there are in exactly 12 g of carbon-12. ■ The Avogadro constant is the number of a stated type of particle (atom, ion or molecule) in a mole of those particles. ■ Empirical formulae sh...
Chemistry问题1:An element is a substance that is made up of only one kind of atoms.One kind是指同一个的atom,还是Metal或者non-metal两大类中的一类?2:an element=an atom?有什麼分别?最好举个例子. 相关知识点: 试题来源: 解析 1.化学元素是根据原子核电荷的多少对原子进行分类的一种方法,把核...
What is the term used to describe a property that is independent of the amount of a substance? What are the characteristics properties of a pure substance? Is the boiling point of a substance a characteristic property? Explain. Can IR and NMR be used to determine the identity and purity ...
Izumi ImaiTakashi Shimojo
58. Our chemistry teacher once said every substance( 物质)___(be) made up of elements(元素).相关知识点: 试题来源: 解析 Our chemistry teacher once said every substance is made up of elements. 1. 句子缺少谓语,需要填入动词。 2. every substance 作主语,谓语动词用单数。反馈...
用Quizlet學習並牢記包含what is the SI unit for mass?、what is the basic unit of temperature in the SI system?、cubic centimeter measures...等詞語及更多內容的單詞卡。
in a water molecule is 2 : 16. No matter how many molecules of water we have, this ratio will always be the same. But the mass of even 1000 atoms is far too small to be weighed. We have to scale up much more than this to get an amount of substance that is easy to weigh...
the mass in grams of 1 mol of a substance Mole the SI base unit used to measure the amount of a substance whose number of particles is the same as the number of atoms of carbon in exactly12 g of carbon-12 Emperical Formula a chemical formula that shows the composition of a compound ...
adsorption- the adhesion of a chemical species onto a surface adulterant- a chemical that acts as a contaminant in the context of another substance's purity. aether- a medium believed to carry light waves in the 18th and 19th centuries. ...