"<span>Changes of state are physical changes. They occur when matter absorbs or loses energy. Processes in which matter changes between liquid and solid states are freezing and </span>melting<span>. Processes in which matter changes between liquid and gaseous states are vaporization, evaporation, and condensation."</span>
<em><u>Protons</u></em><em><u> = Positive Charge</u></em>
<em><u>Neutrons</u></em><em><u> = Neutral Charge/No Charge</u></em>
<em><u>Electrons</u></em><em><u> = Negative Charge</u></em>
<em>This one's simple: electrons have a negative charge, protons have a positive charge and neutrons — as the name implies — are neutral.</em>
<u><em>Protons</em></u>
<em>Elements are differentiated from each other by the number of protons within their nucleus. For example, carbon atoms have six protons in their nucleus. Atoms with seven protons are nitrogen atoms. The number of protons for each element is known as the atomic number and does not change in chemical reactions. In other words, the elements at the beginning of a reaction -- known as the reactants -- are the same elements at the end of a reaction -- known as the products.</em>
<em />
<em><u>Neutrons</u></em>
<em>Although elements have a specific number of protons, atoms of the same element may have different numbers of neutrons and are termed isotopes. For example, hydrogen has three isotopes, each with a single proton. Protium is an isotope of hydrogen with zero neutrons, deuterium has one neutron, and tritium has two neutrons. Although the number of neutrons may differ between isotopes, the isotopes all behave in a chemically similar manner.</em>
<em />
<u><em>Electrons</em></u>
<em>Electrons are not bound as tightly to the atom as protons and neutrons. This allows electrons to be lost, gained or even shared between atoms. Atoms that lose an electron become ions with a +1 charge, since there is now one more proton than electrons. Atoms that gain an electron have one more electron than protons and become a -1 ion. Chemical bonds that hold atoms together to form compounds result from these changes in the number and arrangement of electrons.</em>
Answer:
The minimum volume of the container is 0.0649 cubic meters, which is the same as 64.9 liters.
Explanation:
Assume that ethane behaves as an ideal gas under these conditions.
By the ideal gas law,
,
.
where
is the pressure of the gas,
is the volume of the gas,
is the number of moles of particles in this gas,
is the ideal gas constant, and
is the absolute temperature of the gas (in degrees Kelvins.)
The numerical value of
will be
if
,
, and
are in SI units. Convert these values to SI units:
;
shall be in cubic meters,
;
.
Apply the ideal gas law:
.
The cost of painting the traffic sign of 7.065 square feet is approximately equal to 25 dollar.
<u>Explanation:</u>
The cost of painting the circular traffic sign is given as 3.50 dollar per square feet. The diameter of the traffic sign is 36 inch, then its radius will be
inches.
But as the cost is given in unit of feet, we have to convert the radius from inches to feet.
1 inches = 0.0833 feet
18 inches = 18 × 0.0833 feet
So, the radius of the traffic sign will be approximately equal to 1.5 feet.
The area of the traffic sign will be
square feet.
So, if the cost of painting 1 square feet of traffic sign is 3.50 dollar, then
cost of painting 7.065 square feet of traffic sign = 3.50 × 7.065 = 24.7 dollar.
Thus, the cost of painting the traffic sign of 7.065 square feet is approximately equal to 25 dollar.
Answer:
11·699
Explanation:
Given the concentration of hydroxide ion in the solution is 5 ×
M
Assuming the temperature at which it is asked to find the pH of the solution be 298 K
<h3>At 298 K the dissociation constant of water is

</h3><h3>∴ pH + pOH = 14 at 298 K</h3><h3>pOH of the solution = -log( concentration of hydroxide ion )</h3>
∴ pOH of the given solution = - log(5 ×
= -0·699 + 3 = 2·301
pH of the given solution = 14 - 2·301 = 11·699
∴ pH of the solution = 11·699