O2 gas, where there are two Oxygen atoms which are covalently bonded together
<u>c.</u> 12. preparing data tables and gathering safety equipment
<u>b.</u> 13. reading all instructions before beginning a science lab
<u>a.</u> 14. recognizing what a picture of a hand means
<u>e.</u> 15. wiping your work area with a wet paper towel
<u>d.</u> 16. wearing goggles and an apron
The answer is A. you sre correct!
Answer:
atomic structure
Explanation:
Its pretty obvious. Nothing here can test atomic structure. You can test melting point, with a hot plate. You can test the ability to dissolve something with the container of water. You can test brittleness with the hammer.
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.