Phenolphthalein
In acid it is colourless and in water also colourless
Answer:
Bromine is a chemical element with the symbol Br and atomic number 35. It is the third-lightest halogen, and is a fuming red-brown liquid at room temperature that evaporates readily to form a similarly colored gas.
Answer;
Iodine
Explanation;
Electron configurations are a way of keeping track of the location of the electrons around the nucleus.
Iodine is an element which belongs to the halogen family. The halogen group includes fluorine, chlorine, bromine, astatine, and iodine.
A neutral iodine atom would also have 53 electrons. Its ground state electron configuration would be:
1s22s22p63s23p64s23d104p65s24d105p5
Answer:
A.The concentration of water is greater outside the cell than inside the cell.
Explanation:
The contractile vacuole of certain organisms functions to regulate water flow in and out of the cell. It does this by storing excess water that comes into the cell. In the case of this organism with a filled up contractile vacuole, it means water is flowing into the cell.
Naturally, water will flow into a living cell when an osmotic gradient i.e. difference in concemtration, has been created between intracellular and extracellular solutions. Osmosis involves movement of substances from a region of high water concentration to a region of low water concentration. This means that if water is flowing into the cell, which is stored by the contractile vacuole, the concentration of water must be greater outside the cell than inside.
Answer:
3.91 minutes
Explanation:
Given that:
Biacetyl breakdown with a half life of 9.0 min after undergoing first-order reaction;
As we known that the half-life for first order is:
where;
k = constant
The formula can be re-written as:
Let the initial amount of butter flavor in the food be 
= 100%
Also, the amount of butter flavor retained at 200°C 
= 74%
The rate constant
To determine how long can the food be heated at this temperature and retain 74% of its buttery flavor; we use the formula:
Substituting our values; we have:
t = 3.91 minutes
∵ The time needed for the food to be heated at this temperature and retain 74% of its buttery flavor is 3.91 minutes
