27 I think beacuse if you subtract
Answer :
During diffusion, when the concentration of the molecules on both sides of the membrane is the same, the molecules will continue to move across the membrane in both the direction.
Answer 3 : It allows single-celled organism to reproduce, and other organism to repair damage tissues and grow.
Answer 4: The nucleus is an organelle that is surrounded by the cytoplasm, a jelly-like fluid.
Explanation :
Diffusion : It is a process where liquid moves from higher concentration to the lower concentration through permeable membrane.
When the concentration of the molecules on both sides of the membrane is same and the membrane is permeable membrane then diffusion will occur and the molecules will moves continuously across the membrane in both the direction.
Answer 3 :
Mitosis : It is a process of cell division. In this process, nucleus divides into two daughter cell and each daughter cell contains same number of chromosomes as present in parent nucleus.
The main purpose of the mitosis is to repair damaged tissues and growth.
Answer 4 :
Nucleus is a type of cell organelle. It is present in both animal and plant cells and it is the brain of the cell. It is present only in eukaryotic cell.
Nucleus is an organelle which is surrounded by the cell membrane which protects its from the other cells.
Cytoplasm is a jelly-like fluid which is present in the cell membrane which is made up of salt and water.
Explanation:
4. limestone heat lime + carbon dioxide
The reactants in this expression above is limestone
The products of the reaction is carbon dioxide and lime
Reactant is the species that gives the product and it is usually found on the left hand side of the expression.
The product is the substance on the right hand side of the expression that forms through the experiment.
Heat is used to facilitate the reaction.
5. An exothermic reaction is a reaction in which heat is given off.
An endothermic reaction is a reaction in which heat is absorbed in the process.
An exothermic reaction is always warmer after the reaction whereas an endothermic reaction is colder at the end of the reaction.
6. Sodium salicylate is made from carbon dioxide and sodium phenoxide.
The reactants are:
Carbon dioxide and sodium phenoxide
The product is:
Sodium salicylate
Answer:
No
Explanation:
The pH scale is a scale graduated from 0-14 which shows the degree of acidity of alkalinity of a substance. The pH scale is graduated in such a way that 0-6.9 indicates acidity, 7.0 indicate a neutral substance, while a pH of 8-14 indicates alkalinity respectively.
There are three main definitions of acids/bases
- Arrhenius definition
-Brownstead-Lowry definition
-Lewis definition
Arrhenius explains acids as any substance that produces hydrogen ions as its only positive ion in solution while a base produces hydroxide ions as its only negative ion in solution. The pH scale is based on corresponding values of pH derived from aqueous solutions of these substances.
However, not all acids/bases produces hydrogen or hydroxide ions in solution. Brownstead-Lowry definition of acids and Lewis definition of acids could be extended to nonaqueous media where the pH can not be measured as there are no hydrogen or hydroxide ions present in the solution.
This implies that pH measurement may not apply to acids/bases in the all the categories of acids/bases hence it can not be utilized for all acids and bases.
Arrhenius - sodium carbonate
Brownstead-Lowry - concentrated HF
Lewis acid - AlCl3
