According to the concept of Avogadro's number, there are 1.505×10²³ molecules in 0.25 mole of O₂.
Avogadro's number is defined as a proportionality factor which relates number of constituent particles with the amount of substance which is present in the sample.
It has a SI unit of reciprocal mole whose numeric value is expressed in reciprocal mole which is a dimensionless number and is called as Avogadro's constant.It relates the volume of a substance with it's average volume occupied by one of it's particles .
According to the definitions, Avogadro's number depend on determined value of mass of one atom of those elements.It bridges the gap between macroscopic and microscopic world by relating amount of substance with number of particles.
Number of atoms can be calculated using Avogadro's number as follows: mass/molar mass×Avogadro's number
Number of molecules is obtained by multiplying number of moles and Avogadro's number , that is 0.25×6.023×10²³=1.505×10²³ molecules.
Thus, there are 1.505×10²³ molecules in in 0.25 mole of O₂.
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Chemistry is the study of the properties, composition, and structure of substances, and the transformations they undergo. It also deals with the energy exchanges in these processes. As "The Central Science", chemistry interrelates with numerous other scientific disciplines.
Chemistry, often referred to as "The Central Science", is a branch of science that deals with the properties, composition, and structure of substances (defined as elements and compounds), the transformations they undergo, and the energy that is released or absorbed during these processes. It plays a vital role in multiple disciplines such as biology, medicine and environmental science. It allows us to understand the makeup of substances, from the atomic level to complex molecules, and how they interact through chemical reactions.
One example of a branch of Chemistry is thermochemistry, which focuses on relationships between heat, work, and other types of energy in physical and chemical processes. Dalton's atomic theory, investigating quantitative and qualitative aspects of chemistry, also developed the concept of atomic mass units, allowing for the calculation of formula mass and the quantitative description of substances.
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2. bera particle
3.gamma radiation
4. positron
when the substances are chemically reacted the physical properties remain the same
each substance has a unique set of physical properties
no two substances have any of the same properties
The following statements apply:
1. At any given location, the physical properties of a substance do not change.
2. Each substance has a unique set of physical properties.
Each substance usually has some characteristics that are peculiar to it and these characteristics can be used to identify them and separate them from other materials. Change of location does not affect the properties of substances, thus, the properties of oxygen that is found in America is the same as the one that is found in Nigeria.
(2) absorb protons (4) oxidize
Answer: The nucleus of radium-226 is unstable and hence undergoes decay.
Explanation: Radium has many isotopes. One of them is which has 88 protons and 138 neutrons. It is a radioactive isotope and undergoes decay process.
This isotope undergoes alpha - decay and produces Radon-222 isotope.
Equation for alpha - decay follows:
Hence, the nucleus of radium-226 undergoes decay process.
Please help
Answer:
The water cycle is driven primarily by the energy from the sun.