Answer: A. To change the potential energy of the reactants.
Explanation:
Catalysts make such a breaking and rebuilding happen more efficiently. They do this by lowering the activation energy for the chemical reaction. Activation energy is the amount of energy needed to allow the chemical reaction to occur. The catalyst just changes the path to the new chemical partnership.
Answer:- 1.90 atm
Solution:- It is based on combined gas law equation, PV = nRT
In this equation, P is pressure, V is volume, n is moles of gas, R is universal gas constant and T is kelvin temperature.
If we divide both sides by V then:
We know that, molarity is moles per liter. So, in the above equation we could replace 
by molarity, M of the gas. The equation becomes:
P = MRT
T = 20 + 273 = 293 K
M = 
Let's plug in the values in the equation:
P = 
P = 1.90 atm
So, the pressure of the gas is 1.90 atm.
Answer:
No this statement is false.
Explanation:
when an atom lose or gain the electron ions are formed. If the atom lose an electron the positive ions are formed called cations while anion is formed by the gaining of electron by an atom The elements having less electrons in valance shell usually lose their electrons while the elements like halogens having 7 valance electrons gain an electron to complete the octet. while p block elements noble gases are inert, their outer most valance shell is complete so they do not form ions.
P block elements are non-metals, metals and metalloids. These are thirty five elements. The P-block elements are present on right side of periodic table. There valance electrons are present in P orbital. The p-block metals are shiny and good conductor of heat and electricity. These metal lose the electron which is accept by non metals and form ionic bond. They have high melting points.
Metalloids includes boron, silicon, germanium, arsenic, antimony and tellurium. Metalloids contain both the properties of metals and non metals, Some metalloids are toxic like arsenic.
Most of p-block elements are non metals. They are bad conductor of heat and electricity and have low boiling points. The non metals mostly accept the electron from the metals and usually from ionic bond like in case of chlorine. It form the ionic compound with sodium.
The sodium chloride which is an ionic compound, formed by the complete transfer of electron from sodium to chlorine atom and form ionic bond. In this ionic compound sodium carry positive charge and chlorine carry negative charge there is attraction between these oppositely charged atoms.
