Answer:
<em>The correct option is A) The atom has changed over the years.</em>
Explanation:
Option A is not correct because an atom does not change. It remains the same always. The structure of an atom will always contain neutrons, protons and electrons.
Scientific theories tend to change over time as new information is brought up. Novel techniques lead to more advanced experiments and results. As a result, a scientific theory is subjected to change whenever evidence is found for a new theory which challenges the older one.
The atomic theory has changed many times due to novel scientific techniques and experiments.
Answer : A and D shows PROCESS of sweating
Answer:
The amount of heat required to melt 25 grams of ice is 8,350 Joules or 2,000 calories.
Explanation:
Answer: There are 576.46 number of grams present in 16.95 mol hydrogen peroxide 
.
Explanation:
Number of moles is defined as the mass of substance divided by its molar mass.
The molar mass of 
is 34.01 g/mol. Hence, mass of hydrogen peroxide present in 16.95 moles is calculated as follows.
Thus, we can conclude that there are 576.46 number of grams present in 16.95 mol hydrogen peroxide .
Answer:
If an atom gains or loses an electron, it bacomes an ion. An atom that gains a negative electron, it becomes a negative ion. If it loses an electron it becomes a positive ion
Explanation:
A lithium atom has 3 protons and 3 electrons. It can lose one of its electrons, making it an ion. It now has more positive protons than electrons so it has an overall positive charge. Therefore it is a positive ion.
A fluorine atom will tend to gain, rather than lose, an electron. By gaining a negative electron, it has an overall negative charge. It has become a negative ion.
