Answer:
The freezing point depression of solvent is 0.8265 K.
Explanation:
Mass of glucose = 250 g
Mass of solvent = 20.0 g = 0.020 kg
Molal depression water constant of water, = 1.86 K kg/mol
Molality of the solution =
Normal freezing point of water =
Freezing point of solution =
The freezing point depression of solvent is 0.8265 K.
Answer:
Simple Daltons atomic theroy and Through chemical reactions we can witness their effects. Through mathematical equations combined with indirect observations, we can calculate their various sizes. And finally, with the aid of new technologies such as the Scanning Tunnelling Microscope, atoms can now be seen.
Explanation:
The first accurate theory explaining the nature of matter was Dalton's Atomic Theory: 1. All matter is composed of atoms, and atoms are indivisible and indestructible. Elements are composed of identical atoms, but the atoms of each element are different and distinguishable from each other.(Look up Daltons atomic theroy)
The experiment that used alpha particles to bombard a thin sheet of gold foil indicated that most of the volume of the atoms in the foil is taken up by
Further Explanation:
Rutherford’s experiment:
Rutherford's model of atom is the classic model of the atom instead of having many limitations. He designed an experiment that used alpha particles emitted by radioactive elements as objects that can demonstrate the structure of the atom. Rutherford showed his own physical model for the subatomic structure as a result of the experimental observations.
The postulates of Rutherford’s model are as follows:
1. An atom consists of a positive charge in a very small volume. Most of its mass is concentrated in a very small region of the atom and this region was termed as the nucleus of the atom.
2. The nucleus of the atom is surrounded by the negatively charged particles which were called electron. These electrons were supposed to revolve around the atomic nucleus in a circular path at a very high speed. This circular path is called orbit.
3. A very strong electrostatic force of attraction holds together the negatively charged electrons revolving around the nucleus positively charged concentrated in the nucleus.
Limitations of Rutherford’s model:
1. It did not tell anything about the distribution of electrons in various orbits.
2. This model failed to explain Maxwell’s theory of electromagnetic radiation.
3. It was unable to explain the stability of an atom.
Therefore most of the volume of an atom is taken up by empty space in the atom.
Learn more:
1. The major contribution of Antoine Lavoisier to chemistry: brainly.com/question/2500879
2. Example of physical change: brainly.com/question/1119909
Answer details:
Grade: High School
Subject: Chemistry
Chapter: Atomic Structure
Keywords: Rutherford, atom, volume, nucleus, orbit, postulates, limitations, Maxwell, electromagnetic radiations, distribution of electrons, stability of atom.
Answer:
Researchers at Virginia Tech decided to try using biochar to help reforest the post-mining site soil. They got permission to apply a layer of biochar to a post-mining site before it was reseeded and replanted.
B. metalloid
C. nonmetal
D. noble gas
The element in period 4 and group 1 of periodic table is potassium which is a metal.
An element is said to possess metallic properties if it has 1,2,3 electrons in its valence shell as these number of electrons can be easily removed by supplying less amount of energy .
Elements present in group 1,2,3 have 1,2,3 valence electrons respectively.Hence, these elements are metals and it is a characteristic property of metals to easily loose electrons.
Hence group 1, 2 are metals which comprises the s-block of the periodic table.Metallic properties increases down the group as distance between valence electrons and nucleus increases due to which they can be easily removed.
Metallic propertiesdecrease along a period as electrons are added to same shell and hence cannot be easily removed.
Learn more about metallic properties,here:
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