The tubes 1, 5 and 6 is the answer to the question which test tubes were used to determine the optimal ph lipase activity. Lipase is an enzyme and optimum ph the maximum possible point on which enzyme become active.
Answer is: the oxidation number of oxygen must decrease.
Oxidizing agent is element (substance) that gain electrons in chemical reaction.
For example, balanced chemical reaction: C + O₂ → CO₂.
Oxygen change oxidation number from 0 to oxidation number -2 (reduction) and carbon change from 0 to +4 (oxidation)
Answer:
photosynthesis uses light as energy source,and cell respiration uses chemical energy
Answer:
When liquid water is cooled, it contracts until a temperature of approximately 4 degrees Celsius is reached. After that, it expands slightly until it reaches the freezing point, and then when it freezes it expands by approximately 9%. When water freezes, water molecules form a crystalline structure maintained by hydrogen bonding. Ice is less dense than water because the orientation of hydrogen bonds causes molecules to push farther apart, which lowers the density.
Answer: Correct option is (D).
Explanation:
Given that unknown element has larger atomic radii than potassium atoms and its valence electrons feel an effective nuclear charge of +1 which means that this unknown element belongs to group(I) of the periodic table.
In periodic table:
- As we move down the group the value of ionization energy decreases down the group. This is due to increase in the size of an element.With increase in size valence electrons gets far away from the nucleus by which less energy will require to ionize the element.
- Electronegative characters also decreases when we move down the group.This is due to increase in size of an element by which electrons present in valence shells are far away from the nucleus.
So,It would have lower ionization energies than K and a lower electronegativity value than K.
