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assertion tartaric acid or citric acid is added to baking soda. reason baking soda as on heating it produces na2co3 which is bitter in taste and is injurious to health.

When sodium hydrogen carbonate decomposes when heated, tartaric acid is added to offset the sodium carbonate produced. Tartaric acid is added to... View Article

for propadiene 1 2 3 h2c = c = ch2 , correct statement(s) is / are

We must understand that allenes are carbon molecules that have twofold bonds with each of their two surrounding carbon centres. Allenes are... View Article

the number of atoms present in 16 g of methane is 1) 6.02 × 10’1.5 2) 3.01 × 1024 3) 3.01 × 10’1.5 4) 6.02 × 1023

1) 6.02 × 1023 2) 3.01 × 1024 3) 3.01 × 1023 4) 6.02 × 1024 Answer The molar mass of methane is 16 g/mol. 1 molecule of methane contains 5... View Article

Draw the diagram representing the schematic arrangement of geiger-marsden experimental setup for the alpha particle scattering. define impact parameter, series limit and ionization energy.

The Schematic arrangement of Geiger-Marsdon Experiment (also known as Rutherford Scattering Experiment) is shown below.... View Article

what volume of decinormal k2cr2o7 solution would be needed to convert 1.19 g of tin to stannic chloride in acidic medium?

No.of moles of tin in 1.19g of tin = 1.19/119 n=0.01 as Sn is converting to SnCl4 Thus nf=4 Normality of Kr2Cr2O7 = 0.1N Therefore, 0.1N×V =... View Article

which of the following pairs of d-orbitals have electron density along the axis? * dz², dxz dxz, dyz dz², dx²–y² dzy, dx² y²

From the orbital diagram of d-orbital sit is clear that dx2 - y2 has electron density along x- and y-axis. dx2 - y2 and dz2 orbitals have... View Article

Percentage of Se in peroxidase anhydrous enzyme is 0.5% by weight (At. wt =78.4). What is the minimum molecular weight of peroxidase anhydrous enzyme?

In peroxidase anhydrous enzyme, 0.5 gm Se is present in 100gm of the enzyme. In a molecule of enzyme, one Se atom must be present. Hence 78.4gm... View Article

The product of acid hydrolysis of p and q cannot be distinguished by

Primary alcohol does not react with Lucas reagent at all, whereas tertiary alcohol reacts quickly. This test can be used to distinguish between... View Article

if the roots of equation ax2+bx+c=0 are equal in magnitude but opposite in sign then the value of b will be

Let the two roots be alpha and beta. Alpha=-beta. Alpha + beta =-b/a =-beta+beta = -b/a = 0 = -b/a = -b = 0 = b =0.... View Article

the electronic configuration of a particular neutral atom is 1s²2s²2p63s²3p². what is the number of unpaired electrons in this atom

3 is the answer p has 3 orbitals meaning 3 blanks. Each blank has 2 electrons, up and down. The '3' indicates that the element belongs to the... View Article

how much energy will you get from one gram of glucose

Glucose has a caloric value of four calories per gram. Glucose is the primary component of all carbohydrates.... View Article

how many gram of ice at –10ºc is needed to cool 100 g of water from 25ºc to 10ºc?

Mass of water = 100g Latent heat of fusion of ice = 80 Specific heat of ice = 0.5 Q(hot body) = 100 x 1 x 15 = 1500 Q(cold body) = m(ice) x 0.5... View Article

100ml of 0.1 M NaOH is added to 100 ml of a 0.2 M CH3COOH solution. The pH of resulting solution will be (pka=4.74)

NaOH + CH3COOH ⟶ CH3COONa + H2O Now it is a buffer pH = pka + log[salt/acid] pH = 4.74 + log1 = 4.74... View Article

if rate constant of a first order reaction is 2.31 × 10–3 s–1 and initial concentration of the reactant is 1.6 m then the rate of the reaction after second half life period will be

t1/2 = 0.693/k = 0.693/2.31×10−3 =300s... View Article

In the case of a zero-order reaction, the ratio of time required for 75% completion to 50 % completion is

Its a Zero Order Reaction, Time required for 75% completiont1 = (100−25)/2k = 75/2kt2 = (100−50)/2k = 50/2kRatio of times = 1.5... View Article

assertion( a) the water molecule has a bent or v- shape reason (r) since two of the tetrahedral positions are occupied by lone pairs, water molecule has a bent or v- shape

Both Assertion and Reason are valid, and Assertion is explained correctly by Reason. Water molecules display a bent form. In water molecules,... View Article

van der waals constant (a) for the gases a, b, c and d are 1.25, 3.29, 4.28 and 0.244 respectively. the gas which is most easily liquefied is

Van der Waals forces are weak electric forces that attract neutral molecules in gases, liquefied and solidified gases, and practically all... View Article

number of sp3 carbon atoms, pi bonds and sigma bonds in enol form of acetophenone respectively

In acetophenone, only one sp3 hybridised carbon is present. Acetophenone is an organic chemical with the formula C6H5C(O)CH3 and the molecular... View Article

the equilibrium constant (k) for the reaction 2hi(g) ⇌ h2(g) i2(g) at room temperature is 5.7 and that of 698 k is 2.8 x 10-2. this implies that the forward reaction is

With the increase in temperature, K value decreases, which. means that at high temperature the reaction proceeds in a backward direction or... View Article

The vapour pressure of a liqid solution containing A and B is 99 torr. Colvulate mole % of in vapour phese

P = PA + XB (PB-PA)99 = 100 + XB (80-100)99 = 100 - 20XB20 XB = 1XB = 1/20YB = XB.PB/P= (1/20)x80]/99= 4/99%YB = (4/99)x100= 4%... View Article