Pure metals possess few important physical and metallic properties, such as melting point, boiling point, density, specific gravity, high malleability, ductility, and heat and electrical conductivity. These properties can be modified and enhanced by alloying it with some other metal or nonmetal, according to the need.
Alloys are made to:
Enhance the hardness of a metal: An alloy is harder than its components. Pure metals are generally soft. The hardness of a metal can be enhanced by alloying it with another metal or nonmetal.
Lower the melting point: Pure metals have a high melting point. The melting point lowers when pure metals are alloyed with other metals or nonmetals. This makes the metals easily fusible. This property is utilized to make useful alloys called solders.
Enhance tensile strength: Alloy formation increases the tensile strength of the parent metal.
Enhance corrosion resistance: Alloys are more resistant to corrosion than pure metals. Metals in pure form are chemically reactive and can be easily corroded by the surrounding atmospheric gases and moisture. Alloying a metal increases the inertness of the metal, which, in turn, increases corrosion resistance.
Modify color: The color of pure metal can be modified by alloying it with other metals or nonmetals containing suitable color pigments.
Provide better castability: One of the most essential requirements of getting good castings is the expansion of the metal on solidification. Pure molten metals undergo contraction on solidification. Metals need to be alloyed to obtain good castings because alloys
The molar mass of Calcium hydroxide is 74 g/mol
To find the percent composition we have to find the number of atoms of each element in the formula .
So there’s
Calcium - 1
Oxygen - 2
Hydrogen - 2
Then have to multiply the relative atomic mass of each element by the number of atoms
Ca - 40 g/mol x 1 = 40
O - 16 g/mol x 2 = 32
H - 1 g/mol x 2 = 2
Then To find percent composition of each element we have to divide the mass of each element in the formula by the relative molecular mass of calcium hydroxide
Ca - 40 / 74 x 100 % = 54.0%
O - 32 / 74 x 100 % = 43.2 %
H - 2 / 74 x 100 % = 2.7%
From the options given correct answer is 3rd option
54.0% Ca , 43.0% O and 2.7 % H
Answer is: <span>he boiling point of a 1.5 m aqueous solution of fructose is </span>100.7725°C.
The boiling point
elevation is directly proportional to the molality of the solution
according to the equation: ΔTb = Kb · b.<span>
ΔTb - the boiling point
elevation.
Kb - the ebullioscopic
constant. of water.
b - molality of the solution.
Kb = 0.515</span>°C/m.
b = 1.5 m.
ΔTb = 0.515°C/m · 1.5 m.
ΔTb = 0.7725°C.
Tb(solution) = Tb(water) + ΔTb.
Tb(solution) = 100°C + 0.7725°C = 100.7725°C.
Yes because she is holding the weight of the box.
