1. C. Linus Pauling
2. C. chemistry
3. A. atom
4. D. protons, neutrons and electrons
5. B. positively
6. A. negatively
7. C. uncharged
8. D. carries a charge
9. C. Au
10. D. protons in the nucleus
11. A. atoms
12. B. the pull of gravity on matter
13. C. protons
14. C. 112
15. C. symbols
16. D. compounds
17. C. sodium chloride salt
18. C. solids, liquids, and gases
19. A. the gaseous state
20. C. a number and a unit
21. B. the weight of an object
22. D. 1,000
23. C. 100
24. B. uncertain
25. D. 4
26. A. 1
27.C. 2.26 x 102
28. C. 5 x 10-3
29. C. atomic number
30. A. 5 g/cm3
31. D. temperature
32. C. meter
33. B. 2.2
Answer:
Light receptors within the eye transmit messages to the brain, which produces the familiar sensations of color. Newton observed that color is not inherent in objects. Rather, the surface of an object reflects some colors and absorbs all the others. We perceive only the reflected colors.
Answer:
4 protons, 5 neutrons, 2 electrons
Explanation:
If you look at the numbers beside Be²⁺, the number 9 is the relative atomic mass and the number 4 is the proton (atomic) number. The relative atomic mass is the sum of the number of protons and the number of neutrons.
Number of protons= proton number.
Hence, number of protons= 4
Number of protons + neutrons= 9
4 + number of neutrons= 9
number of neutrons
= 9 -4
= 5
In an atom, the number of protons and electrons are the same since atoms are electrically neutral. But in an ion, the number of electrons is not equal to the number of protons since the atom gains/ loses electrons to form an ion. A positive sign means that electrons are given away.
Thus, Be gives away 2 electrons to form Be²⁺.
Original number of electrons= 4
Number of electrons in Be²⁺
= 4 -2
= 2
In summary, the number of protons and neutrons in an ion is the same as that of the atom. However, the number of electrons is not the same.
A barometer is used to measure the pressure in the air, Like if there was a Storm coming the barometer can forecast (Predict) The weather in the air
