Solvent- generally in liquid form – are used to dissolve, suspend or extract other materials, usually without chemically changing either the solvents or the other materials. this means the answer is A
A is the answer I know bc I take biology
Answer:
this is answers to the second picture
Explanation:
1- energy
2- structure
3- reaction
4- substance
5- reactants
6- products
7- changed
8- At first there is no reaction because of the protective oxide coating on the aluminum. But soon an exothermic reaction between bromine and aluminum causes brown fumes of bromine to be given off. But as a new substance, aluminum bromide is produced. White smoke is produced.
9- heated to 120 degrees Celsius it melts and first forms a pale-yellow liquid.
In this form the atoms are covalently bonded, and the liquid can flow easily. However, heated up beyond 150 degrees Celsius, the result is a dark red
10- When a chemical change occurs it is more difficult to revert the substance back to its original state. (To be honest I don't know)
Three of the functions of proteins are as antibodies, as enzymes and as messengers. As antibodies, they protect the cells from diseases ie they fight diseases. As enzymes, they regulate the chemical reactions within cells, and thirdly they transmit signals as messengers such as hormones do in co-ordinating biological processes. Proteins are so diverse because of their unique 3-D structures which their polymers form from the 20 amino acids available as their building blocks.
When reversing a given reaction, we simply change the sign of the standard enthalpy change value. Therefore, the reaction will become:
H₂O → H₂ + 0.5O₂, ΔH = 286kJ
This is because if a certain amount of energy is released when a reaction occurs, the same amount of energy must be supplied for the reaction to occur in the reverse direction.