Answer:
The period 4 alkaline-earth metal has the name Calcium. An isotope of this element having 20 neutrons has a mass number of 40.
Explanation:
Looking at the periodic table 4th row for the alkaline-earth metal, we can find Calcium which has an atomic number of 20 (or protons number, or z). The mass number is given by the sum of protons and neutrons. If the number of protons in this case is 20 and the number of neutrons is also 20, the mass number A = 40.
Answer: picture is work for # 1,2,4,5,7
Explanation: number 3: as the pressure in the volume decreases, the volume increases causing it to expand and eventually blow.
number 6: because the temperature and the amount of gas don’t change, these terms don’t appear in the equation. What Boyle’s law means is that the volume of a mass of gas is inversely proportional to its pressure. This linear relationship between pressure and volume means doubling the volume of a given mass of gas decreases its pressure by half.
hope this helps :))
Atoms are divisible contrary to the early beliefs that the smallest "indivisible" matter is an atom. When an atom loses its identity it means that they are divisible. Atoms chemically react with other kinds of atoms thus changing their activity.
They certainly are not that important to our lives, but it’s good to know :)
Answer:
T2 = 550K
Explanation:
From Charles law;
V1/T1 = V2/T2
Where;
V1 is initial volume
V2 is final volume
T1 is initial temperature
T2 is final temperature
We are given;
V1 = 20 mL
V2 = 55 mL
T1 = 200 K
Thus from V1/T1 = V2/T2, making T2 the subject;
T2 = (V2 × T1)/V1
T2 = (55 × 200)/20
T2 = 550K