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What else can I help you with?
What substance is used to test for starch?
The presence of starch can be tested with the help of Iodine. Similarly Benedict's test solution is also used to detect the presence of starch.
What type of food will give a negative Iodine test and a positive Biuret Solution test?
An iodine test is used to test for the presence of starch (or polysaccharides, specifically amylose or amylopectin). A Biuret solution test is used as an indicator for peptide bonds within proteins. Therefore, if you get a negative iodine test and a positive Biuret test, you would probably be testing a animal food source (beef, chicken, pork). Overall, any food that doesn't have starch present within it would be appropriate to use. Hope this helps!
List the steps of the gram-staining procedure in order and fill in the color of gram-positive cells and gram-negtive cells after each step?
____________Color of Gram-positive_______Color of Gram-negativePrimary stainCrystal violet_____Purple____________________ PurpleMordant:Iodine____________Purple________________________PurpleDecolorizing agent:Alcohol-acetone__ Purple____________________ ColorlessCounterstain:Safranin___________Purple_________________________Red
Iodine and Benedict's solution were both used to test for certain nutrients in a sample of food If both tests were positive for the nutrients the sample must contain?
Both iodine and Benedict's solution test for different nutrients in the sample. Iodine is used to test for the presence of starch, while Benedict's solution is used to test for the presence of reducing sugars like glucose. Therefore, if both tests are positive, the sample must contain both starch and reducing sugars.
What is the liqudi called when testing for starch?
The liquid used to test for starch is called iodine solution. Iodine solution turns a blue-black color in the presence of starch.
What is the indicator for carbohydrates?
Simple(sugar): benedicts solution. Turns bright orange. Complex(starch): iodine turns dark purple/black
Why would a negative iodine test for starch indicate a positive result for the enzymatic degradation of starch by amylase?
A negative iodine test for starch indicates that the starch has been broken down by amylase into simpler sugars, such as maltose or glucose, that do not react with iodine. Therefore, the absence of a starch-iodine complex formation suggests that amylase has successfully degraded the starch substrate.
What color is gram negative stain and gram positive stain if you forget to apply iodine?
If iodine is not applied, both the gram-positive and gram-negative stains will appear to be gram-negative. The iodine acts as a mordant that helps to fix the crystal violet stain in the gram-positive bacteria, making them appear purple. Without iodine, the crystal violet stain can be easily washed out of both gram-positive and gram-negative bacteria, resulting in a pink or red color.
Is iodine a positive or negative charge?
No, nitrogen is more electronegative than iodine. Electronegativity of nitrogen= 3.04 Electronegativity of Iodine = 2.66
What solution is use to test starch?
Iodine-KI reagent. Add to the substance being tested directly. Result: If positive, Turns Blue/Black If negative, (absence of starch) Solution remains orange/yellow.
What substance is used to test for starch?
The presence of starch can be tested with the help of Iodine. Similarly Benedict's test solution is also used to detect the presence of starch.
What type of food will give a negative Iodine test and a positive Biuret Solution test?
An iodine test is used to test for the presence of starch (or polysaccharides, specifically amylose or amylopectin). A Biuret solution test is used as an indicator for peptide bonds within proteins. Therefore, if you get a negative iodine test and a positive Biuret test, you would probably be testing a animal food source (beef, chicken, pork). Overall, any food that doesn't have starch present within it would be appropriate to use. Hope this helps!
What does lugol's iodine?
it is iodine and potassium iodide solution It's a orange colored solution that consists of Iodine and Potassium Iodide and is used to test a substance for starch. If the color of the solution turns black when put on/in the substance, then the substance is positive for starch.
Diff between gram's iodine and iodine?
iodine& grams iodine Gram's iodine is a solution of 2% iodine and 3% potassium iodide in 70% ethanol. Gram's iodine is also used as a forensic toxicology reagent for the detection of alkaloids, as a source of iodine for iodometric titrations, as an indicator for the presence of starch, and as a general laboratory source of iodine/iodide. This solution is laboratory grade, and not for medicinal use. Iodine is non metallic,dark gray,lustrous,solid element
Is iodine solution ionic?
A solution of iodine is covalent.
What is the difference between strong iodine solution and weak iodine solution?
their color
Would the iodine solution change colour when it is tested on a slice of bread?
No, iodine solution will not change color when tested on a slice of bread. Iodine solution reacts with starch, turning it blue-black. Bread does not contain starch in high enough amounts to produce a noticeable color change.
