Answer: All apply
The periodic table is an arrangement of the chemical elements in the form of a table, ordered by:
-Their atomic number (number of protons)
-Their configuration of electrons
-Their chemical properties
It was progressively developed over time as the scientific knowledge advanced; for this reason many modifications and corrections might be done in the future.
Its usefulness lies in the fact that it allows the existing elements to be organized in a more structured and coherent way, according to the chemical properties they possess. Dividing the table into rows and columns, which represent the periods and groups or families.
Then, with the location and classification of an element according to its group, we can determine how it acts by knowing its chemical and physical characteristics.
This is how with this configuration can be distinguished 4 sets of chemical elements, according to the ease of their atoms to lose or gain electrons, transforming into ions: metals, semimetals, non-metals and noble gases.
This has helped to predict the existence of various elements that have not yet been discovered, because by elements already located in the table and the periodicity found, <u>there are still empty spaces that indicate the composition of the element that has not yet been found</u>.
In addition, this table helps to simplify in some way the teaching of chemical elements and facilitates their learning, as well as their usage in the development of technological innovations.
Answer:
a = 2.3 m/s²
T = 45 N
Explanation:
Draw a free body diagram for each mass.
For the mass on the incline, there are four forces:
Weight force mg pulling down.
Normal force N perpendicular to the incline.
Friction force Nμ pushing down the incline.
Tension force T pulling up the incline.
For the hanging mass, there are two forces:
Weight force Mg pulling down.
Tension force T pulling up.
Sum of the forces on the hanging mass in the -y direction:
∑F = ma
Mg − T = Ma
T = Mg − Ma
Sum of the forces on the sliding mass in the perpendicular direction:
∑F = ma
N − mg cos θ = 0
N = mg cos θ
Sum of the forces on the sliding mass in the parallel direction:
∑F = ma
T − mg sin θ − Nμ = ma
Substitute:
Mg − Ma − mg sin θ − mgμ cos θ = ma
Mg − mg (sin θ + μ cos θ) = ma + Ma
Mg − mg (sin θ + μ cos θ) = (m + M) a
a = [ Mg − mg (sin θ + μ cos θ) ] / (m + M)
Plug in values:
a = [ 6.0×9.8 − 5.0×9.8 (sin 30° + 0.20 cos 30°) ] / (5.0 + 6.0)
a = 2.3 m/s²
Now find tension:
T = Mg − Ma
T = 6.0×9.8 − 6.0×2.3
T = 45 N
Answer:
Semi-conservative
Explanation:
Each strand of the original DNA molecule serves as a template for the production of its counterpart
It depends.. it might have to due with environmental changes.
