what is the diff between atoms and molecule?

What is the difference between O2 and 2O?

50 names of compounds and their chemical formula

what mass of oxygen will contain same number of molecules as 2.5moles ofchlorine,Cl2 ?

Define mole concept?

what are the limitations of dalton's atomic theory?

if 1g of carbon contains x atoms,what will be the number of atoms in 1 g of magnesium?

gve list of monovalent cations/anions

diavalent cations /anions

trivalent cations/anions.

which postulate of daltons atomic theory can explain the law of definite proportion?

calculate the mass of 1 molecule of of oxygen gas : given [at mass of o = 16u,N_A =6.022 * 10²³ mol ^-1]

how many moles are there in each one of the following?

(A)19.0 atoms of fluorine.

(B) 280 g of silicon

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

how to calculate the valency of any compound?

The mass of one atom of an element X is 2.0 x 10^-23 g

Calculate the atomic mass of element X

What could element X be

how can we find the valency of polyatomic ions like SO4, SO3, CO3,PO4 etc.?

The formula of compounds formed by following ions.

Cr³⁺ and SO_{4 ^2-}

Pb²⁺ and NO_3^1-

 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.

what is the number of molecules in 0.25 moles of oxygen gas?

valency table

calculate the no. of aluminium ions present in 0.051g of aluminium oxide

 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

a)1.032x10²² 

b)1.032 x 10²³

c)3.88 x 10²²

d)1.302 x 10²²

and pls explain

give me a list of atomicity of all elements

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

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.

prove the formula K.E.=1/2mv²

Q. How many molecules are present in 1 ml of water..? explain

calculate the molar mass of CO2, H2SO4, NaCl?

(ii) 0.1 mole of H2SO4

III) 10 to the power of 23 molecules of CO2gas

(iv) 1 gram of carbon

(v) 10 to the power of 23 atom of calcium

(Atomic masses : Ag =108 u ,N=14u ,S=32u ,Ca=40u)

Experts, please solve the question by specific formulae and please solve it only with help of specific formulae. Plzzzzzzzzzz...........

I want all elements' symbols with their valencies and atomicity.

what is meant by tetra atomic and poly atomic?

How many atoms are there in 16 gram of oxygen?

Calculate the number of moles in 52 g of helium gas ?

1 g of silicon contains ' n' atoms. how many atoms are there in 0.8 g of calcium?

what are polyatomic ions?give examples

• Which has more number of atoms? 100g of N2 or 100g of NH₃

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 what is the difference between nitrate,nitride,nitrite?

 what were the drawbacks of Daltons atomic theory?

How much Ca is present in the total amount of Ca(NO₃)₂ that contains 20 g of nitrogen?

Calculate the molecular mass of potassium permanganate (KMnO4). Atomic masses: K=39.0u,

Mn=55.0u, O=16.0u.

if one mole of carbon atoms weighs 12g what is the mass of 1 atom of carbon?? plss explain....

Why is the valency of Phosphate three? explain.

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?

what is the atomicity of phosphorous?and valency?

 calculate the number of molecules in 11g of CO2....

sm1 plshelp me with this!!!

why atomic mass of some element  are in fraction

calculate the number of molecules present in a drop of chloroform (CHCl3) weighing 0.0239g.

explain dalton's atomic theory and write its drawbacks

WHat do the symbols H₂,S & O₄ mean in the formula H₂SO_4?

Is there any trick to learn Valency?

How to solve numericals based on the mole concept?

Calculate the number of molecules of phosphorus [P4] present in 31 gram of phosphorus.

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 ?

Why is valency of magnesium 2? How can we find the valency of an atom?

calculate the number of moles in 22g of carbondioxide?

The number of oxygen atoms in 20 grams of sulphur trioxide is same as that present in X grams of ozone . The atomic mass of sulphur and oxygen are 32u and 16u respectively . find the value of X.

Calculate mass of 3.011 X 10 ²³no of nitrogen atoms ( atomic mass of N = 14 u)

What is the volume of oxygen required for the complete combustion of 4 litres of ethane ?

a) 4 litre b) 12 litre c) 8 litre d) 14 litre

give 2 examples of polyatomic elements

(1) the composition of their nuclei.

(2) their electronic configurations.

(3) give the reason why the two isotopes of magnesium have different mass

numbers.

difference between molecular mass formula unit mass.

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)

DEFINE MOLE CONCEPT & ITS FORMULAS?

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Is there any difference between molar mass and molecular mass?If yes then how

Sample A contains one gram molecule of oxygen molecule and sample B contains one mole of oxygen molecule. What is the ratio of the number of molecules in both the samples.

If the aluminium salt of an anion is Al2X3, what is the valency of X and what will be the formula of magnesium salt of X?

Convert into mole.

(a) 12 g of oxygen gas

(b) 20 g of water

(c) 22 g of carbon dioxide

In a reaction, 10 g of calcium carbonate reacts with 7.3 g of hydrochloric acid. The products of reaction are 11.1 g of calcium chloride, 1.8 g of water and 4.4 g of carbon dioxide gas. Show that these observations are in agreement with the law of conservation of mass.

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.

GIVE AN EXAMPLE OF 1] DIATOMIC 2] TRIATOMIC MOLECULE OF COMPOUNDS

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

What is the difference between 2N and N₂ ?

what do we call those particles which have more or less electrons than a normal atom?

what are alkalis give 2 examples

what is the differences between 2H and H₂ ?

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 )

Calculate the mass of one atom of sodium.