18
In chemistry, a group is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table; the f-block columns are not numbered.
Answer:
The amount of heat required to melt 25 grams of ice is 8,350 Joules or 2,000 calories.
Explanation:
1.strong acid: 2
2.weak acid:6
3.strong base:13
4.weak base:8
5.neutral:7
Answer:
Metals:
Copper: to make cooking utensils such as pots because it has a high heat conductivity.
Aluminium: to make aluminium foil / soda cans because it is malleable
Mercury: fills up thermometers because it can indicate the temperature when it expands. But it is toxic so fewer people are using mercury thermometers now.
Titanium: to make the body of supersonic aircrafts because it is strong and corrosion resistant
Gold: to make jewelry because it is shiny and also corrosion resistant
Non-metals:
Nitrogen: to fill up chip packages because its molecules are unreactive
Helium: to fill up balloons because it is lightweight
Hydrogen: for generating electricity in hydrogen fuel cells. It is environmentally-friendly because it does not produce any greenhouse gas or toxic pollutants.
Fluorine: added in toothpaste for strengthening the teeth. It can also prevent cavities.
Carbon: the graphite in pencils. this is one form of carbon. Other common forms (allotropes) of carbon include diamond and Buckminsterfullerene (buckyball).
Yes, people should be concerned because plaque buildup might cause your breath to smell bad, or cause your teeth to look very yellow, consider brushing your teeth and using mouth wash daily and don’t drink or eat unhealthy foods that will cause your teeth to look bad. plaque buildup might also cause damage to the stomach and maybe affect when you have to use the restroom.
