There are 12.052 ×10²³ atoms in 54 g of aluminium according to the concept of Avogadro's number.
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
Substituting the values in the formula,54/26.98×6.022×10²³=12.052×10²³ atoms .
Hence, there are 12.052×10²³ atoms in 54 g of aluminium.
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Answer:
Susana's red crystal sample is a compound because it was broken down into a gas and blue powder. It is not an element because elements cannot be broken down into simpler substances by ordinary means, such as heating.
Explanation:
The red crystals heated by Susana are a compound because they released a gas and turned into a blue powder when heated, indicating a chemical change.
The sample of red crystals that Susana heated up is a compound, not an element. We can come to this conclusion because when the sample was heated, a gas was released and a different substance, a blue powder, was left behind.
This indicates a chemical change had occurred, where the original substance decomposed into different substances. Compounds are known to break down into simpler substances or elements under certain conditions.
An example similar to this would be when blue copper sulfate loses water and becomes white upon heating, or when mercury(II) oxide is heated and decomposes into mercury and oxygen.
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Answer:
A pH less than 7 is an acid, with number 1 indicating stronger acids
Explanation:
The pH scale has a range of 1 to 14. The following has been concluded on the pH scale:
1. Between 1 and 6 indicates an acid solution.
2. 7 indicates a neutral solution
3. Between 8 and 14 indicates an alkaline or basic solution.
Now with these information, we can answer the above questions as follow:
A pH less than 7 is an acid, with number 1 indicating stronger acids
A pH less than 7 is an acid. Lower pH values mean stronger acids.
A pH less than 7 is considered an acid. The pH scale measures the concentration of hydrogen ions in a solution, therefore a lower number on the scale indicates a higher concentration of hydrogen ions and consequently a stronger acid. For example, lemon juice, with a pH of around 2, is much more acidic than black coffee, which has a pH of about 5.
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OB 1s22s22p63s23p6
OC 1s22s22p63s2305
OD 1s22s²2p63s23d10452
Answer:
1s2 2s2 2p6 3s2 3d5 is a pseudo-noble-gas electron configuration
Explanation:
It is the technetium with atomic number 43. Being the lightest element having isotopes with all radioactive and no one are more stable as compared to that of technetium which is in fully ionised state i.e. 97 Tc. This element is mostly used for gamma ray emission in medical treatment. Also found to be used as corrosion inhibitor in case of steel, when present in small amount gives better result. This metal is silver grey colour that is found to discoloration when comes in contact with moist air. Its isotopes are radioactive.
Answer:
1s2 2s2 2p6 3s2 3p6 3d10
Explanation:
A pseduo noble gas configuration refers to charged species with electron configurations that are almost identical to that of one of the noble gases.
The noble gas (n-1)d^10 (where n refers to the principal quantum number of the outer s orbital) configuration of ions is commonly known as a pseudo noble gas configuration. The configuration stated in the answer is for Cu^+ ion. n in the case of Cu^+ ion is 4(since copper metal has a 4s1 level).
Note that; 1s2 2s2 2p6 3s2 3p6 is the electron configuration for argon, followed by 3d^10. Hence our definition for a pseudo noble gas.
Hydrogen is a nonmetal that does not exhibit properties such as malleability or ductility. Hydrogen is a unique element in the universe and its physical and chemical properties differ markedly from malleable or ductile elements, such as metals. Thus, hydrogen is neither malleable, ductile, nor brittle.
Hydrogen is a unique element in the universe, and its physical and chemical properties differ significantly from those of elements that are classified as malleable or ductile, such as metals. Properties such as being shiny, malleable, and ductile are characteristics of metals which can be deformed without breaking or drawn into wires, and they conduct heat and electricity well. However, hydrogen is a nonmetal and under normal conditions, it is relatively inactive chemically. It does not demonstrate properties like malleability or ductility as metals do. Hence, hydrogen is not malleable, ductile, or brittle.
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The given quantity of any substance is an important aspect of it merging with other substances. The smaller the particles the less is the surface area exposure.
Thus smaller particles have less surface area.
Learn more about the smaller and have generally dissolve faster.
brainly.ph/question/11958399.
Answer:
For many solids dissolved in liquid water, the solubility increases with temperature. The increase in kinetic energy that comes with higher temperatures allows the solvent molecules to more effectively break apart the solute molecules that are held together by intermolecular attractions.