Search:

Which trisaccharide can Beta-galactosidase convert it into maltose and galactose ?


I hope to find help in this question

Which trisaccharide can Beta-galactosidase convert it into maltose and galactose ?


I hope to find help in this question

from where you get 0.8720 ?








I didn't understand this point. .

Hi everybody. .

I have also another 2 Q. . I hope that I get help. .



1- A 0.8720g sample of a mixture cinsisting solely of sodium brpmide and potassium bromide yields 1.505g of silver...

That's oK. . You did what you have to. .

Thanks again. .

Thanks a lot. .

I did what you said and I get 14%

I have 2 Q in my HW I can't solve them .
the first one I did not understand it ,the second I tried but I failed



1- An aqueous solution contains NaNO3 and KSCN . The thiocyanate ion is...

10 mL -> 4x10^-4 mol
1 mL -> 4x10^-4 / 10 = 4x10^-5 mol
250 mL -> 4x10^-5 * 250 = 0.01 mol

mass (Na2CO3) : (106) (0.01 ) = 1.06 g

percentage purity = (1.06 / 1.5 ) * 100 = 70.6%


Thanks...

n = C * V
C= 4*10 ^-4 / 10 = 4*10^-5

n = (4*10^-5) ( 0.25) = 1*10^-5

mass (Na2CO3) : (106) (1*10^-5) = 1.06*10^-3 g

percentage purity = (1.06*10^-3 / 1.5 ) * 100 = 0.07 %

So it will be the same equation

Na2CO3 + 2HCl... > 2NaCl + H2O + CO2

no.of moles (HCl) : (4 ml)(0.2) = 8 *10^-4

no.of moles (Na2CO3) : 8 *10^-4/ 2 = 4 *10^-4

mass (Na2CO3) : (106) (4...

Na2CO3 + 2HCl... > 2NaCl + H2O + CO2

(0.167 / 0.3215) * 100 = 52 %


The second I did not know how can I write the balancw equation

I tried on first one. .

Na2CO3 + HCl... > 2NaCl + H2O + CO2

no.of moles (HCl) : (27.92)(0.1131) = 3.157

no.of moles (Na2CO3) : 3.157 / 2 = 1.578

mass (Na2CO3) : (106) (1.578) =...

1- what is the percentage of sodium carbonate in a sample of 0.3215 g. If 27.92 ml of 0.1131 M HCl were needed to titrate the sample




2- A 1.5 g of soda ash sample was dissolved in 250 mL...

Hello. .

I have Q could anybody help me to solve it ?


How can I derive an expression for the expansion coefficient of A non-perfect gas ?

mmm , I dont know . .

Yaaa it help. .

Thanks. .

Thanks a lot , but how u get 5.6 times " what do u mean 648 go into 3.6?".. I didn't understand this point. .

Thanks,

I have to explain why the compound will dissolve. .

So how can I know that 0.17g can be dissolved in 1mL of water ? I mean how you know it will dissolve ?

Calculate the number of mL of HCl reagent (36.0%, specific gravity = 1.18) that are needed to prepare one liter of 0.1M HCl solution. .


Thanks advance. .

Listed below are solubility vs temperature data for an organic compound in water.

temp. sol. In 10 mL water
0 0.15 g
20 ...

The PH of 0.1M MCl (M^+ is an unknown cation ) was found to be 4.7. Write the ionic equation for the hydrolysis of M^+ and its corresponding equilibrium expression Kb . Calculate the value of Kb

d) That's mean it will shift in the right..

3) I didn't understand

Ok thanks for your helping in first one , and I will try to solve the second Q

Could you check ?

a) no effect

b) shift to the right to decrease the # of NO2

c) no effect because no H+...

Could anybody help me to understand this Q ?

BaSO4 <........> Ba^2+ + SO4^2- , △H >0

In which direction will the equilibrium shift if

a) H2SO4 is added ? Why ?

b) BaCl2 is added...

Could anybody help me in this HW


A piece of metal weighing 5.10g at a temperature of 48.6C was placed in a calorimeter into 20mL of water at 22.1C ,and the final equilibrium temperature was...

1) How many joules are required to change the temperature of 50g of water from 23.3C to 47.6C ?


2) If the specific heat of methanol is 2.51J/K-g, how many joules are necessary to rise the...

a) The area of parallel -plate capacitor is 5.0 cm^2 and is filled completely with Teflon. If the separtion between the plates is 2.6mm, what is the maximum energy that can be stored before break...

I like the subject of the Ester , but when I serch I didn't find anything..

Did you have any link about it ?

Could anybody help me to choose interesting topic to do my presentation in organic chemistry ? :rolleyes:

Could you please help me to complete this equation , I get the major product but I didn't how to write others.. :confused:



1- Al^3+ + NH4Cl + 3NH4OH... > Al(OH)3 +

2- Ni^2+ + ...

I like your explaining , so a lot thanks for your effort .

In 2(a) I converted I to moles , but from where can I get its volume ?


In the b I get [2.25] and when I converted to grams I get...

1) Phosphorus trichloride gas and chlorine gas react to form phosphorus pentachloride gas

PCl3 + Cl2 ......> PCl5

A gas vessel is charged with a mixture of PCl3 (g) and Cl2 (g) , which is...

Thanks a lot , your explanation was very strong and clear..

1- NO2^- + KMnO4 ------> KNO2 + MnO4

2- S2O3^2- + 2HCl ------> SO2 + S + Cl^- + H2O

3- S2O3^2- + 2AgNO3 ------> Ag2S +2NO3


the last one I can't solve it
I wait your checking

Ok , I will try after my classes finish today

Thanks a lot

Thanks a lot , its clear now

yes I think the equation was right

about the 4th Q I get the correct answer

Thanks a lot , its clear now

yes I think the equation was right

about the 4th Q I get the correct answer

I tried to solve my homework , but I face some problem Im not sure about it and another I can't solve it..


Im not sure about the solve , could you check if it is right or wrong

1- (Salt +...

Thanks for your helping and have a nice dream


I mean in the second one that if we change the concentration of S2O8 how this change will effect in the reaction..



The third Q: I get the...

Nobody want help me?! :(

S2O8 + 2I >>> I2 + 2SO4



what effect does doubling the concentration of iodine have on the rate of this reaction ?


what effect does changing the [S2O8] have on the reaction ?

Thanks a lot for your helping..

I solve Q1

The result was 0.099mol/L

What about another Q (2,3) , how can I solve it ?

Thanks for your helping..

I did't understand what you explain

Na2C2O4 and you write H2C2O4 . Why ?

1) If 0.4586g of sodium oxalate,Na2C2O4, requires 34.53 ml of KMnO4 solution to reach the end point , What is the molarity of the KMnO4 solution ?


2) Titration of an oxalate sample gave the...

*The mame sec-butyl alcohol defines a specific structure but the name sec-penty alcohol is ambiguous . Explain


*write the structure and give the IUPAC systematic name of an alkane or...

Suggest a way to determine whether a colorless liquid is pure water or a salt solution without tasting it

Compound C is asymmetric , has molecular formula C5H10O , and contains two methyl groups and a 3 functional group . It has a broad infrared absorption band in the 3200-3550 cm-1 region and no...

Two isomers having molecular formula C4H6O are both symmetrical in structure . In their infrared spectra , neither isomer when in dilute solution in CCl4(used because it is nonpolar ) has absorption...

Write structural function for each of the following :

a)three ethers with formula C4H10O

b)A secondary alcohol with the formula C3H6O

c)Three secondary alkyl halides with the formula...