Answer:
SiO2(s) + 3C(s) ------> SiC(s) + 2CO(g)
Explanation:
The formula for silicon oxide is SiO2 and carbon is C. silicon carbide is SiC
and carbon monoxide is CO.
An arrow is always used to separate the reactants (left) and products (right).
A balanced equation must contain equal number of atoms in each side of the equation.
For example in the equation above, there are 1 atom of silicon appears on each side; 2 atoms of oxygen and three atoms of carbon.
The number of half -lives that has passed after 105 hours for krypton-79 that has half-life of 35 hours is calculated as below
if 1 half life = 35 hours
what about 105 hours = ? half-lives
= (1 half life x105 hours) /35 hours = 3 half-lives has passed after 105 hours
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
