Answer:
No
Explanation:
The same amount of matter is present before and after chemical and physical changes. Matter cannot be created or destroyed
Answer:
Water, 35 liters. Carbon, 20 kilograms. Ammonia, 4 liters. Lime, 1.5 kilograms. Phosphorous, 800 grams. Salt, 250 grams. Saltpeter, 100 grams. Sulfur, 80 grams. Fluorine, seven-point-five. Iron, five. Silicon, three grams. And trace
amounts of 15 other elements.
the ingredients of the average adult,right down to the last specks of protein in your eyelashes. And even though science has given us the entire physical breakdown, there's never been a successful attempt at bringing a human to life. There's still something missing. Something scientists haven't been able to find in centuries of research. ...and in case you're wondering, all those ingredients can be bought on a child's allowance. humans can be made rather cheap. There's no magic to it.
Answer : The molecule
is a polar molecule.
Explanation :
Polar molecule : When the arrangement of the molecule is asymmetrical then the molecule is polar.
Non-polar molecule : When the arrangement of the molecule is symmetrical then the molecule is non-polar.
The given molecule is, 
The electronegativities of oxygen and fluorine are different. The molecular geometry of
is bent. As, Fluorine is more elctronegative than the oxygen. So, the arrows putting towards the more electronegative element i.e, fluorine. These arrows do not balance each other. Due to this, the asymmetrical arrangement of these bonds makes the molecule polar.
Hence, the given molecule
is polar.
Answer:
a. 4 sig figs
b. 3 sig figs
c. 2 sig figs
Explanation:
A chemical reaction is defined as the reaction in which bonds between the reactants either break or form which leads to the formation of a new substance.
For example, 
So, when we drop a sodium metal into water then it produces a frizzing sound which shows the metal is reacting with water.
We know that when two aqueous solutions chemically react with each other then it may lead to the formation of an insoluble substance which is known as precipitate.
This means that formation of a precipitate is also a chemical reaction.
Thus, we can conclude that following are the statements which show evidence for a chemical reaction.
- Dropping sodium metal into water produces fizzing.
- Mixing two aqueous solutions produces a precipitate.