Answer:
N and P
Explanation:
Anion:
When an atom gain the electrons anion is formed. The negative sign shows that atom gain electron because number of electron are greater than protons or we can say that negative charge becomes greater than positive charge.
Cation:
When atom lose electron cation is formed. The atom thus have positive charge because number of positive charge i.e protons are increased are greater than negative charge or electron.
In given problem N and phosphorus both can gain three electrons which means negative charge becomes greater that's why the extra electron gained by atoms are written as -3 and both form anion with charge -3.
while Al form cation with charge +3 Mg form cation with charge +2 and iodine and bromine both form anion with charge of -1.
Answer:
Which sequence of events is required to form a limestone cave where you can walk around and observe cave formations, such as stalactites? (Note: stalactites hang from the ceiling - they have to hold on tight to the roof.)
A geological sequence of events as involving the lowering of the water table to expose cave structures where stalactites and stalagmites form which is described as follows,
Explanation:
1. Acidic percolated water formed cavities of solution beneath the natural water table known as phreatic zone
2. After the passage of time there is a drop in the water table dropped forming caves from cavities
3. These caves, which are air filled voids that contains adequate environment for forming stalactites and stalagmites and where they are found
Answer:
The weigth of a 90kg man standing on the moon is <u><em>147.6 N (option C)</em></u>
Explanation:
Weight is called the action exerted by the force of gravity on the body.
The mass (amount of matter that a body contains) of an object will always be the same, regardless of where it is located. Instead, the weight of the object will vary according to the force of gravity acting on it.
The formula that allows you to calculate the weight of any body is:
W = m*g
where:
- W = weight measured in N.
- m = mass measured in kg.
- g = acceleration of gravity measured in m/s². The acceleration of gravity g is the same for all objects that fall due to gravitational attraction, whatever their size or composition. For example, as an approximate value on Earth, g = 9.8 m/s².
In this case, the mass m has a value of 90 kg and the gravity g has a value of 1.64 m/s², which is the value of the acceleration of gravity of the moon. Then:
W=90 kg* 1.64 m/s²
<u><em>W= 147.6 N</em></u>
Finally, <u><em>the weigth of a 90kg man standing on the moon is 147.6 N (option C)</em></u>
Hydrogen mass is 1, the atom with mass number 7 is Lithium