Answer:
A circle graph, or a pie chart, is used to visualize information and data. A circle graph is usually used to easily show the results of an investigation in a proportional manner. Bar graphs are used to compare things between different groups or to track changes over time. However, when trying to measure change over time, bar graphs are best when the changes are larger.
Explanation:
In short, bar graphs are better to keep track of data over long periods of time, and circle graphs are better when you are trying to visualize a specific set of data.
Atoms 'like' to have 8 valence electrones. sodium has one electron 'in excess' and chlorine 'lacks' in one. so they just exchange :) both are happy. then the ionic bond is formed because chlorine is now charged negative (additional electron) and sodium is charged positive (gave up one electrone) - the opposite charges cause electrostatic pull. many atoms, many bonds and thats how salt is built.
Answer:
ten atoms of hydrogen are present in one mole of caffeine.
Explanation:
Molecular formula of caffiene is given which is C3H10N4O2. It clearly shows that ten atoms of hydrogen are present. One mole is amount equal to one molecular weight of a molecule which is derived from molecular formula. So as moecular formula has ten atoms of hydrogen, one mole of caffeine has 10 atoms of hydrogen.
Answer: Belongs to the group 2A
Explanation:
As you can see, the first two ionization energies are close and low, meaning that this element ionizates easily.
Not only loses easily the first electron, but the second too
To remove the third electron you requiered a huge amount of energy
Now, elements easily ionizable are the ones from group IA, group 2A and transition metals.
The last ones have mixed characteristics in matter of how many electrons you can remove from them, so they are not a family.
Now the question: group I or group II ?
The elements of group I have low ionization energies for the first electron but high energies for the second ones.
Being all that said, the unknown element belongs to the Group 2A
