Answer: A
Explanation
The digestive tract carries out the function of peristalsis by moving food through the system. Peristalsis also removes excess liquid from the body. Chemical digestion breaks down food into small nutrients, but this process does not involve peristalsis. Finally, absorption of nutrients into the blood does not fall under the purview of peristalsis.
Ammonia is NH3. The molar mass of NH3 is 17.0307g.
(1.2*10^3)/17.0307=70.46 moles of NH3.
If you are using significant figures, it is 70. moles of NH3.
Answer:
2KClO3 -------> 2KCl + 3O2
Explanation:
First, in balancing a chemical reaction such as the one given in the question, you should understand that for an equation to be balanced, the number of atoms and ions on both sides of the equation that is the right and left side must be equal. This follows the law of conservation of mass which tells us that matter can neither be created nor destroyed but can be changed into another form.
Next is to begin balancing the equation by identifying and writing down the substances given:
KCl03 ---------> KCl + O2
Next is to count he number of the individual atoms on each side and find out if they are the same on both sides and if not you must follow the next step.
Add a corresponding number and use it to multiply the atoms involved
KClO3 ---------> KCl + O2
Oxygen is 3 on the left side and two on the other side, so we multiply the left hand side by 2 and the right hand side by 3
2KClO3 -----> KCl + 3O2
The potassium and Chlorine are no longer balanced, so you multiply the right had=nd side of KCl by 2.
2KClO3 -----> 2KCl + 3O2
The reactionis herefore balanced as both sides have equal number of atoms and ions.
Answer:B or C
Explanation: when a scientist forms a hypothesis he or she usually makes an prediction or a statement about what will happen next in an sequence of events
Answer:
Explanation:
There are 118 different known <em>elements</em>.
Each element is identified by the number of protons and it is called the atomic number. For instance, the atomic number of hydrogen is 1, every hydrogen atom has one proton; the atomic number of oxygen is 8, every oxygen atom has 8 protons; the atomic number of carbon is 6, every carbon atom has 6 protons.
There are not two different elements with the same atomic number (number of protons).
The 118 known elements are listed in the periodict table in groups (columns) and periods (rows) in increasing order of atomic number (number of protons).
So, by counting the number of protons of an atom, chemists can tell the element to which the atom belong.
