Select Board & Class
what is the diff between atoms and molecule?
in HNO3 the valency of hydrogen is 1 and valency of NO3 is 2 then why it is written HNO3 in place of H2NO3
50 names of compounds and their chemical formula
Calculate the number of molecules of phosphorous (p4) present in 248g of solid phosphorous. ( given atomic mass of phosphorous=31.0u No=6.022x1023 per mole )
Define mole concept?
What do you mean by atomicity of the molecule of an element?
what are the limitations of dalton's atomic theory?
How many atoms are present in one molecule of ozone?
gve list of monovalent cations/anions
diavalent cations /anions
Find the mass of 12.044 x 1023 atoms of megnesium.
(given -> atomic mass of Mg =24.0u)
calculate the mass of 1 molecule of of oxygen gas : given [at mass of o = 16u,NA =6.022 * 1023 mol -1]
how do we know the presence of atoms if they do not exist independently for most of the elements?
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
Give the atomicity of carbon dioxide, oxygen, ozone, solid sulphur....
how can we find the valency of polyatomic ions like SO4, SO3, CO3,PO4 etc.?
1. A sample of ammonia weighs 3 grams. what mass of sulphur trioxide contains the same number of molecules as are in 3 grams of ammonia???
2. A spoonful of sugar contains 6 grams. If you dissolve 2 spoonful of sugar for a cup of tea, calculate the no. of sugar molecules in cup.......
how to calculate the valency of any compound?
Find the mass of oxygen contained in 1 kg of potassium nitrate (KNO3)
a) 475.5g b) 485.5g c) 475.3g d) 485.2g
calculate the molar mass of nitric acid HNO3 (H=1,N=14,O=16)
In which case hydrogen atoms are more
1. 2 moles of HCL
2.1 mole of NH3.
Calculate the mass of 1 atom of silver and 1 molecule of carbon dioxide.
if 1 g of sulphur dioxide contains x molecules, how many molecules will be present in 1 g of oxygen????????????
calculate the no. of ions of aluminium in 0.056g of aluminium oxide.
calculate the no. of aluminium ions present in 0.051g of aluminium oxide
Why are Dalton's symbols not used in Chemistry
give me a list of atomicity of all elements
What is the mass of 0.5 mole of Cl2 gas?
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
what happens in the reaction flask?
do you think that a chemical reaction has taken place?
why should we put a cork on the mouth of the flask?
does the mass of the flask and it s contents change?
prove the formula K.E.=1/2mv2
What is the mass of 10 moles of water ?
calculate the molar mass of CO2, H2SO4, NaCl?
how can you conclude that electron are fundamental particles
what is meant by tetra atomic and poly atomic?
How will you prove experimentally the law of conservation of mass?
I want all elements' symbols with their valencies and atomicity.
Give the name of any two elements present in the following compounds: Baking powder, common salt, sulphuric acid.
Calculate the number of moles in 52 g of helium gas ?
what is the difference between ionic compounds and molecular compounds?
what are polyatomic ions?give examples
what is neon?cation or anion
what is the difference between nitrate,nitride,nitrite?
define atomic mass unit?how it is linked with relative mass unit?
what were the drawbacks of Daltons atomic theory?
144 grams of pure water is decomposed by passing electricity. 16 grams of hydrogen and 128 grams of oxygen are obtained. Which chemical law is illustrated by this statement?
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 the difference between O2 and 2O?
if one mole of carbon atoms weighs 12g what is the mass of 1 atom of carbon?? plss explain....
how many moles are there in 5g of calcium?(calcium=40u
why atomic mass of some element are in fraction
if 1 mole of nitrogen molecules weighs 28 g , calculate the mass of one molecule of nitrogen in grams........
what is the atomicity of phosphorous?and valency?
The visible universe is estimated to contain 1022 stars. How many moles of stars are present in the visible universe?
explain dalton's atomic theory and write its drawbacks
can any of u guyz plzz explain mole concept to me??
n d ans of dis q..
How many molecules are present in 6 g of hydrogen?
Is there any trick to learn Valency?
are a few postulates of dalton wrong?
How to solve numericals based on the mole concept?
Calculate the number of molecules of phosphorus [P4] present in 31 gram of phosphorus.
.Relative atomic mass of an element A is 16.2.There are 2 isotopes with mass no.16 and 18 respectively of the element. Calculate the percentage of these 2 isotopes present in the element.
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 ?
what is variable valency and write its cause???????
Why is valency of magnesium 2? How can we find the valency of an atom?
5 gram of calcium combines with 2 gram of oxygen. Find the molecular formula of this compound.
calculate the number of moles in 22g of carbondioxide?
Calculate mass of 3.011 X 10 23no of nitrogen atoms ( atomic mass of N = 14 u)
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.
Q. How many molecules are present in 1 ml of water..? explain
What is the atomicity of sodium ? Please help me out...It is urgent !
give 2 examples of polyatomic elements
human have 2 arms and an octopus have 8 arms if 1 octupus has to catch hold of a few people in such manner that all arms of the octupas and the both hands of humans are locked how many human do you think the octupus can hold?
difference between molecular mass formula unit mass.
what is an atom?
DEFINE MOLE CONCEPT & ITS FORMULAS?
what is meant by mole concept ?explain
Is there any difference between molar mass and molecular mass?If yes then how
Are the molar mass and the molecular mass the same?
Convert into mole.
(a) 12 g of oxygen gas
(b) 20 g of water
(c) 22 g of carbon dioxide
we had exam and this was one of the question:
an element X has valency 3 write the formula of its oxide .
can i get the ans
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.
I dont really understand mole concept...finding mole fom massfinding mole from number of particles mass from mole of moleculemass from mole of atommass from number of particlesnumber of particles from massnumber of molecules from massnumber of particles from given moles
GIVE AN EXAMPLE OF 1] DIATOMIC 2] TRIATOMIC MOLECULE OF COMPOUNDS
What is the difference between 2H and H2?
Plss Answer me..
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
any1 play pc gamez like cod4?
What is the difference between 2N and N2 ?
i did not understand what are alpha particles ? plz xplain
What is the atomicity of –
(a) Ozone (b) Nitrogen
(c) Neon (d) Sulphur
what are alkalis give 2 examples
There are 2 isotypes (ie. same elements with different mass nos.) of carbon (c-12 and c-14) .c-14 is considered a bit unstable so c-12 is taken as the standard unit .
what is the differences between 2H and H2 ?
Q. calculate d mASS OF IODINE AND SODIUM CHLORIDE..........
Calculate the mass of one atom of sodium.
Q1. Give an example of polyatomic molecule of an element.
Q2. What is different between an atom and a molecule?
Q3. Calculate the mass of 0.5 mole of nitrogen into gas.
Q4. What is molar mass?
Q5. Calculate the molar mass of carbon dioxide gas.
Copyright © 2021 Applect Learning Systems Pvt. Ltd. All rights reserved.
E.g: 9876543210, 01112345678
We will give you a call shortly, Thank You
Office hours: 9:00 am to 9:00 pm IST (7 days a week)