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what is the diff between atoms and molecule?
which postulate of daltons atomic theory can explain the law of definite proportion?
50 names of compounds and their chemical formula
Define mole concept?
two elements x and y combine to form xy in the ratio of 1:35.5 by mass. what mass of y combine with 2 grams of x ?
what are the limitations of dalton's atomic theory?
What is the difference between O2 and 2O?
gve list of monovalent cations/anions
diavalent cations /anions
1. how many individual atoms are there in each of the following ? (a) 32 moles of sulphur (b) 32g of sulphur (c) 32u of sulphur (S = 32) 2. how many moles are there in each of the following ? (a) 280g of silicon (b) 12.044 x 10^25 atoms of phosphorus (c) 19.0 atoms of fluorine 3. One mole of zinc atoms weigh 65g. calculate the weight of one atom of zinc.
calculate the mass of 1 molecule of of oxygen gas : given [at mass of o = 16u,NA =6.022 * 1023 mol -1]
Calculate the number of molecules of sulphur (S8) present in 16 g of solid sulphur.
In this question why do we multiply the avagadro number? We are to find number of molecules, so why we take out moles?????????????? plzzzzzz reply
In an experiment 1.288g of copper oxide was obtained from 1.03g of copper. In another experiment 3.672g of copper oxide obtain from the 2.938g of copper. Show that these figures verify the law of constant proportion.
how to calculate the valency of any compound?
how can we find the valency of polyatomic ions like SO4, SO3, CO3,PO4 etc.?
how many moles of O2 are there in 1.20 * 1022 oxygen molecules????
calculate the molar mass of nitric acid HNO3 (H=1,N=14,O=16)
Calculate the mass of 1 atom of silver and 1 molecule of carbon dioxide.
names of the elements present in the following compounds:
obtained.Which chemical law is illustrated by this statement?
calculate the no. of aluminium ions present in 0.051g of aluminium oxide
give me a list of atomicity of all elements
Calculate the number of molecules of phosphorus [P4] present in 31 gram of phosphorus.
From 200 mg of CO2 ,1021 molecules are removed.How many moles of CO2 are left ?
a) 0.288 b) 2.88 c) 0.00288 d) 0.0288
prove the formula K.E.=1/2mv2
What does the following denote 2N , N2 , 2N2 , N.
calculate the molar mass of CO2, H2SO4, NaCl?
I want all elements' symbols with their valencies and atomicity.
what is meant by tetra atomic and poly atomic?
Calculate the number of moles in 52 g of helium gas ?
What is the difference between 2N and N2 ?
what are polyatomic ions?give examples
what is the number of molecules in 0.25 moles of oxygen gas?
what is the difference between nitrate,nitride,nitrite?
what were the drawbacks of Daltons atomic theory?
The number of oxygen atoms required to combine with 14 gm of nitrogen to form N2O3( 2 and 3 are in subscript) when 80% of nitrogen is converted to N203( 2 and 3 are in subscript)
if the isotopic distribution of C-12 and C-14 is 98% and 2% respectively, the number of C-14 atoms in 12 g of carbon is
b)1.032 x 1023
c)3.88 x 1022
d)1.302 x 1022
and pls explain
what is meant by symbol of an element?explain with examples
if one mole of carbon atoms weighs 12g what is the mass of 1 atom of carbon?? plss explain....
what is the atomicity of phosphorous?and valency?
why atomic mass of some element are in fraction
A ball is dropped from a height of 10m. If the energy of the ball reduces by 40% after striking the ground, how much high can the ball bounce back ?
explain dalton's atomic theory and write its drawbacks
Why is the valency of Phosphate three? explain.
Is there any trick to learn Valency?
The mass of one molecule of a substance is 11.79 X 10-26 kg. What is its molar mass? What could be the substance?
How to solve numericals based on the mole concept?
If we assume 1/24th part of mass of carbon instead of 1/12th part of it as 1 amu , then mass of 1 mole of a substance will :A) remain changedB) get doubledC) get halvedD)can't be predicted
in HNO3 the valency of hydrogen is 1 and valency of NO3 is 2 then why it is written HNO3 in place of H2NO3
Why is valency of magnesium 2? How can we find the valency of an atom?
calculate the number of moles in 22g of carbondioxide?
give 2 examples of polyatomic elements
The ratio by the number of atoms for water will always be H : O = 2 : 1. Thus, 18 g of water contains 2 g of hydrogen and 16 g of oxygen.
i can understand that the ratio of h = 2 so 2 g of hydrogen contained in the water but why we have taken the oxygen as 16 g but it is given that the ratio of o = 1 pls explain i need you help experts pls.
Calculate mass of 3.011 X 10 23no of nitrogen atoms ( atomic mass of N = 14 u)
define mole. What are the two things that a mole represents
difference between molecular mass formula unit mass.
Calculate the molecular mass of potassium permanganate (KMnO4). Atomic masses: K=39.0u,
DEFINE MOLE CONCEPT & ITS FORMULAS?
Is there any difference between molar mass and molecular mass?If yes then how
Convert into mole.
(a) 12 g of oxygen gas
(b) 20 g of water
(c) 22 g of carbon dioxide
Relative density of gold is 19.5.The density of water is 1000kg/m3.what will be the density of gold in S.I unit and in g/cc.
calculate number of molecules of oxygen in 6.4g of oxygen?
Q. How many molecules are present in 1 ml of water..? explain
GIVE AN EXAMPLE OF 1] DIATOMIC 2] TRIATOMIC MOLECULE OF COMPOUNDS
calculate the ratio of atoms present in 5g of magnesium and 5g of iron...?
(Atomic mass of Mg=24u , Fe=56u )
Chlorophyll contains 2.68% of magnesium by mass.Calculate the number of magnesium atoms in 3.00 g of chlorophyll
a) 1.98 * 1021 atoms b) 6.023 * 1023 atoms c) 1.7 * 1020 atoms d) 2.8 * 1022 atoms
samvad lekhan between 2 friends on
how many moles are there in each one of the following?
(A)19.0 atoms of fluorine.
(B) 280 g of silicon
what are alkalis give 2 examples
what is the differences between 2H and H2 ?
what is the name given to the shorthand representation of an element
Calculate the mass of one atom of sodium.
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