Answer:
12.4 mol O2
Explanation:
4Al + 3O2 -----> 2Al2O3
from reaction 4 mol 3 mol
given 16.5 mol x mol
x = 16.5*3/4 =12.4 mol O2
Everything around us undergoes some changes. The changes can be either physical or chemical. The cutting of hair is an example of physical change.
The physical change is defined as the type of change in which the physical properties of matter such as colour, state of matter, odour, solubility, etc. change. During this change neither the composition nor the chemical nature of the substance is changed.
In a physical change the molecules rearrange among themselves without affecting the internal composition. The chemical property of a substance is not affected by the physical change. But in chemical change the chemical composition of the matter change.
When you cut your hair, some of it is removed it is still your hair. The hair is altered somehow but remains the same substance. Hence it is a physical change. Other examples are cutting paper, melting of ice, etc.
Thus cutting your hair is a physical change.
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According to the concept of Avogadro's number there are 6.023×10²³ elementary entities in an element which when multiplied by atomic mass gives the mass of 1 mole of an element.
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.
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B. mitochondria
C. rough ER
D. ribosome
Answer:
b. mitochondria
Explanation:
Most of the ATP produced in the cells, come from the mitochondria, or even in the cytoplasm. In the case of the protein synthesis, since the process starts inside the nucleus of the cell and ends in the cytoplasm, the energy used during the process are obtained mainly from the mitochondria.