Bonjeur monseur, la french are here! it seems you have a problem with the elements on earth. lead seems correct since it is indeed a harmful material
Answer:
That unknown substance is water
Explanation:
Answer:
The volume is 59, 3 liters. See the explanation below, please
Explanation:
STP conditions (standard) correspond to 273K of temperature and 1 atm of pressure. These values are used and the volume is calculated, according to the formula:
PV = nRT
1 atm x V= 2, 65 moles x 0, 082 l atm/K mol x 272 K
V= 2, 65 moles x 0, 082 l atm/K mol x 272 K/1 atm = 59, 3 liters
The correct answer is B. Chewing in the mouth breaks food into small pieces.
Explanation:
In physical changes, substances do not change their chemical composition or properties but only physical features such as this. This occurs during the chewing because the action of chewing only makes food to be broken down in smaller pieces but does not change its identity, composition, or properties. This does not occur once the food is in contact with saliva, the acid in the stomach, etc. because in these cases, the food reacts with other substances and a chemical reaction occurs, which changes food's identity and composition.
