Answer: C. no new substances
are formed<span>
</span><span>
<span>In the
physical change of matter, there is no new substance that is formed. It is only
the appearance of the matter that is being changed and not its chemical
composition. Cutting, tearing and grinding are only some of the examples that
exhibit physical change. </span></span>
Answer:
Explanation:
What we need to do here is to determine the ratios by using the Rydberg equation starting with the transition to n1 = 1, 2,3, etc and see which one fits the data. Remember the question states that they are series and the wavelengths will be for increasing energy levels.
1/λ = Rh x ( 1/n₁² - 1/n₂²)
Lyman series ( n₁=1 and n₂= 2,3 etc) for the first two lines, the ratios will be:
1/λ₁ /1/λ₂ =(1/1 -1/ 2²) / (1/1 -1/ 3²) ⇒ 0.84 ≠ 0.74 (the first ratio)
For Balmer series n₁ = 2 and n₂ = 3,4,5, etc
1/λ₁ /1/λ₂ =(1/4 -1/3²) / (1/4 -1/4²) ⇒ 0.741 = 0.741 (match!)
Lets use the third line to check our answer:
1/λ₁ /1/λ₂ =(1/4 -1/3²) / (1/4 -1/5²) = 0.66
Cocaine selectively blocks sodium channels which is the mechanism that leads to local anesthetic effects.
Voltage gated sodium channels play very important roles in the body as they are responsible for action initiation and propagation in excitable cells, such as nerves, muscles and neuroendocrine cells. Like other sodium ion channels blockers such as lidocaine, Cocaine selectively blocks sodium ion channels which denies entry of sodium ions in the cell, thus leading to local anesthetic effects.
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.
