Answer:I think this is right: 1. 6 2. 12 3. 4 4. In the middle 5. Carbon 1. The one on the right 2a. Beryllium 2b. Aluminium
Explanation:The protons are the circles with plus signs and the black ones are nutrons. I looked on my periodic table for the rest.
Im a bit torn here, lets look at the definitions of physical and chemical changes:
physical change changes only the phase/state of a substance, but not what the substance is
chemical change is a chemical reaction where a new substance is formed and energy is given off or absorbed.
(it just started raining and it smells really nice out my window)
clearly, this cannot be just a physical reaction. i think i would be inclined to pick B. but C. could have merit as an answer too. sorry for the ambiguity x
Answer : The value of new volume is, 50.0 mL
Explanation :
Boyle's Law : It is defined as the pressure of the gas is inversely proportional to the volume of the gas at constant temperature and number of moles.

or,

where,
= initial pressure at STP = 1 atm
= final pressure = 4.00 atm
= initial volume at STP = 200.0 mL
= final volume = ?
Now put all the given values in the above equation, we get:


Therefore, the value of new volume is, 50.0 mL
Heat is energy, and that energy would eventually cause the object to undergo a phase change.
Mass number = protons + neutrons
mass number = 5 + 7
mass number = 12