Is it multiple choice or do you just answer
Answer:
B.) If sodium carbonate is added to vinegar, the reaction will absorb heat.
Explanation:
A.) is incorrect because this is not testable. Rather, it is just an opinion that cannot be proven correct or incorrect.
B.) is correct because this statement is testable. Tests need to be run to determine the accuracy of the statement.
C.) is incorrect because this statement explains something that does not need to be tested. It is an example of a physical change when one tears a piece of paper.
D.) is incorrect because this is already a true statement. It is obvious that not all reactions absorb/release heat. While tests could be run to further prove this statement true, it is already considered accurate.
Answer:
Yes, Mass is conserved.
Explanation:
Every chemical reactions obey the law of conservation of mass. The law of conservation of mass states that in chemical reactions, mass is always constant.
Equation:
2Na + Cl₂ → 2NaCl
From the equation above, one can observe that the reaction started using 2 atoms of Na and it produced 2 atoms of the same element in NaCl. A molecule of Cl produced 2 atoms of Cl in the NaCl
Design a simple experiment to support your answer:
Aim: To demonstrate the law of conservation of mass
One Na atom weighs 23g
Two Na atom will weigh 2 x 23 = 46g
1 atom of Cl is 35.5g
1 molecule of Cl containing two atoms of Cl will weigh 2 x 35.5 = 71g
Total mass of reactants = mass of 2Na + 1Cl₂ = (46 + 71)g = 117g
On the product side, Mass of 1 NaCl = 23+ 35.5 = 58.5g
Two moles of NaCl will give 2 x 58.5g = 117g
Since the mass on both side is the same, one can say mass is conserved.
PH + pOH = 14
pH + 8 = 14
pH= 6
Answer:
1s² 2s² 2p⁵
Explanation:
The elements of group 17 are called halogens. These are six elements Fluorine, Chlorine, Bromine, Iodine, Astatine. Halogens are very reactive these elements can not be found free in nature. Their chemical properties are resemble greatly with each other. As we move down the group in periodic table size of halogens increases that's way fluorine is smaller in size as compared to other halogens elements. Their boiling points also increases down the group which changes their physical states. i.e fluorine is gas while iodine is solid.
Properties of fluorine:
1. it is yellow in color.
2. it is flammable gas.
3. it is highly corrosive.
4. fluorine has pungent smell.
5. its reactions with all other elements are very vigorous except neon, oxygen, krypton and helium.
6. Its atomic number of 9.
7. its atomic mass is 18.99 amu.
Electronic configuration:
₉F = 1s² 2s² 2p⁵