Answer:
John Dalton
Explanation:
Dalton's atomic theory was the foundation for a new understanding of chemical structures. He proposed that matter was constituted by indivisible and indestructible particles "atoms." He theorized that all atoms of a particular substance were equal, and the atoms of different substances had atoms of different sizes and masses.
He also proposed that all compounds of elements were combinations of elements but in a very precise ratio.
I would say A not 100℅ thou
Answer:
The half-life is 
Explanation:
Using the decay equation we have:

Where:
- λ is the decay constant
- A(0) the initial activity
- A is the activity at time t
We know the activity decrease by a factor of two in a one hour period (t = 1 h), it means that


Taking the natural logarithm on each side we have:


Now, the relationship between the decay constant λ and the half-life t(1/2) is:




I hope it helps you!
Answer:
new volume = 30.513L
Explanation:
V1 =17L , P1= 2.3atm , T1=299K , T2=350K , P2 =1.5atm, V2=?
To find the new volume of the gas we will use the combined gas law.
The combined gas law combines Boyle's law, Charles law and Gay-Lussac's law. Its states that the ratio of the product of pressure and volume to temperature is equal to a constant. its expressed mathematically below.




V2 =30.513L