Physical properties are those properties which ______ measured or observed ______ changing the identity or the composition of the substance
Physical properties are those which can be measured or observed without changing the identity or composition of the substance.
According to the law of conservation of mass, a balanced chemical equation has
According to this total mass of reactants = total mass of product so no. of atoms of each element in reactant is equal to no. of atoms of that element in product
The molar mass of Al2O3 is
Molar mass = 2(27) +3 (16) = 102g.
For the reaction
Fe2 O3 (s) + 3 CO (g) → 2 Fe (g) + 3 CO2,
224 g of CO is available to react with 400 g Fe2O3, the yield of iron and CO2, are:
Moles of CO =8 moles Moles of Fe2O3= 2.5 moles.
3 moles of CO is needed for 1 mole of Fe2O3 so 8 moles of CO will require 2.66 mole of Fe2O3 so Fe2O3 is limiting reagent.
1 mole of Fe2O3 produce 2 mole of Fe so 2.5 mole of Fe2O3will produce 5 mole of Fe = 280g of Fe.
Also 1 mole of Fe2O3 also produce 3 mole of CO2 so 2.5 mole of Fe2O3 will produce 7.5 mole of CO2=330g.
SI units for Base Physical Quantities of length, mass and current are
m,Kg, A are SI units.
Molarity is defined as
Molarity is defined as no. of moles of solute present per litre of solution.
The molar mass of C6H10O5 is
Molar mass = 6(12) + 10(1) + 5(16) = 162g
A measured temperature is 1000F on Fahrenheit scale, then what is this reading be on Celsius scale:
C-0/100-0 = F-32/180.
C/5= F-32/9.
C/5= 100-32/9.
C/5= 68/9.
C= 68×5/9.
C= 340/9.
C= 37.77.
C= 37.8
SI unit of density is
Density = mass/volume. SI unit of mass is kg and that of volume is m3
The calculation of masses (sometimes volumes also) of the reactants and the products involved in a chemical reaction is called
The calculation of masses (sometimes volumes also) of the reactants and the products involved in a chemical reaction is called stoichiometry.
The molar mass of CaCO3 is
Molar mass = 40 + 12 + 3(16) = 100g
There are ____ in 12.0 ml?
Since we know that 1litre -1000ml 1ml-1\1000litre So,12ml-1/1000×12=12/1000 =0.012
Molarity of NaOH in a solution prepared by dissolving 4 g of NaOH in enough water to form 250 ml of solution is:
The kelvin scale is related to celsius scale by
K = °C + 273.15
Molecular mass of glucose (C6H12O6) is
Molecular mass will be = 6(12) + 12(1) + 6(16) = 180u.
The molar mass of AgNO3 is
Molar mass of AgNO3 = mass of Ag + N + O3 = 107.87 + 14 + 3* 16 = 107. 87 + 14 + 48 = 169.87 g
The molar mass of ZnSO4 is
Chemical Formula: ZnSO4
Molar Mass: 161.47 g/mol (anhydrous)
How many atoms of hydrogen are in 67.2 L of H2 at STP?
One mole of any gas at STP has a volume of 22.4 L. So first determine the number of moles of gas you have.
67.2/22.4 = 3 moles of H2
One mole of any substance contains Avogadro's number of atoms = 6.022 x 1023 atoms.
So multiply number of moles x number of atoms/mole = 1.8066 x 1024 atoms of H2.
In scientific notation for such numbers, any number can be represented in the form N × 10n where
n can vary from to 10 and can be +ve or –ve.
Choose the most appropriate answer amongst the options given below for the statement.
A solution of a desired concentration is prepared by diluting
Stock solution is diluted to prepare the solution of desired concentration.
How many atoms of Oxygen are there in 18g of water?
(Hint: Avogadro’s Number = 6.02 x 1023 atoms/mol)
18g H2O = 1mol water = 6.02 x 1023 molecules of water = 6.02 x 1023 atoms of oxygen.
Chemistry does not play a major role in
Chemistry does not deal in explaining superconductivity.
If a matter has definite volume and definite shape, then it is:
Solid
Holds shape
Fixed Volume
Liquid
Shape of Container
Free Surface
Fixed Volume
Gas
Shape Of Container
Volume of Container
Explanation:
Solid is the only state of matter that has a definite shape and definite volume.
The number of moles of solute present in 1 kg of solvent is called:
Molality is defined as no. of moles of solute present per kg of solvent.
There are ____ in 0.05 ml?
1L=1000mL so 0.00005L=0.05mL.
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