<h2>Answer : Law of conservation of mass</h2><h3>Explanation :</h3>
The law of conservation of mass states that in any reaction mass is neither created nor lost it has to remain constant in a system.
In this case, when the reaction setup was done in normal way the mass was lost in surrounding was not considered nor being calculated; whereas when the reaction was studied in a closed system where the gas was collected after the reaction the mass changes was noted down which helped to prove the point of law of conservation of mass and energy.
One can consider an example of soda can where the carbonated drink contains pressurized carbon dioxide gas. when opened the gas bubbles gets lost into the surroundings and we don't measure the mass changes. Instead if the soda can was opened in such a way where the gas evolved was measured then the mass changed would remain the same.
Answer:
See detailed answer with explanation below.
Explanation:
Valence electrons are electrons found on the outermost shell of an atom. They are the electrons in an atom that participate in chemical combination. Recall that the outermost shell of an atom is also referred to as its valence shell. Let us consider an example; if we look at the atom, sodium-11, its electronic configuration is 2,8,1. The last one electron is the valence electron of sodium which is found in its outermost or valence shell.
Positive ions are formed when electrons are lost from the valence shell of an atom. For instance, if the outermost electron in sodium is lost, we now form the sodium ion Na^+ which is a positive ion. Positive ions possess less number of electrons compared to their corresponding atoms.
Negative ions are formed when one or more electrons is added to the valence shell of an atom. A negative ion possesses more electrons than its corresponding atom. For example, chlorine(Cl) contains 17 electrons but the chloride ion (Cl^-) contains 18 electrons.
In molecular compounds, a bond is formed when two electrons are shared between the bonding atoms. Each bonding atom may contribute one of the shared electrons (ordinary covalent bond) or one of the bonding atoms may provide the both shared electrons (coordinate covalent bond). The shared pair may be located at an equidistant position to the nucleus of both atoms. Similarly, the electron may be drawn closer to the nucleus of one atom than the other (polar covalent bond) depending on the electro negativity of the two bonding atoms.
The electrons are shared in order to complete the octet of each atom by so doing, the both bonding atoms now obey the octet rule. For example, two chlorine atoms may come together to form a covalent bond in which each chlorine atom has an octet of electrons on its outermost shell.
Answer:
See explanation
Explanation:
(a) The handspan is the distance between the tip of the thumb and tip of the little finger when the hand is fully stretched.
b) It is impossible for them to obtain an accurate result by the use of a handspan because it doesn't use any standard unit for measurement. It is entirely subjective and highly prone to human errors.
c) Anupam is quite intelligent and active
Answer:
1.23 × 10³ N
Explanation:
Step 1: Given and required data
- Mass of the person (m): 125 kg
- Acceleration due to the gravitational force (g): 9.81 m/s²
Step 2: Calculate the force acting between the Earth and a 125-kg person standing on the surface of the Earth
We will use Newton's second law of motion.
F = m × g
F = 125 kg × 9.81 m/s²
F = 1.23 × 10³ N
If they were connected at one time than you would expect to find similar rock structures because they eroded, weathered, and we’re formed most likely at the same time out of the same material. So basically since they were near each other they were under the same or similar conditions.