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:
500cal
Explanation:
Given parameters:
Mass of water = 50g
Initial temperature = 22°C
Final temperature = 32°C
Specific heat of water = 1cal/g
Unknown:
Amount of heat absorbed by the water in calories = ?
Solution:
To solve this problem, we use the expression below:
H = m c Ф
H is the amount of heat absorbed
m is the mass
c is the specific heat capacity
Ф is the temperature change
H = 50 x 1 x (32 - 22) = 500cal
Explanation:
1. Force=mass*acceleration
acceleration=force/mass
=100/50
=2m/s^2
2. Gravitational force for downward acceleration= mg-ma=m(g-a) , since a is less than g,
So it will be= 50(9.8-2)
=50(7.8)= 390N
Answer:
Part (i) work required to pump the contents to the rim is 281,913.733 lb.ft
Part (ii) work required to pump the liquid to a level of 5ft above the cone's rim is 426,484.878 lb.ft
Explanation:
The center of mass of a uniform solid right circular cone of height h lies on the axis of symmetry at a distance of h/4 from the base and 3h/4 from the top.
Center mass of the liquid Z = (24-19)ft + 19/4 = 5ft + 4.75ft = 9.75 ft
Mass of liquid in the cone = volume × density (ρ) = ¹/₃.π.r².h.ρ
where;
r is the radius of the liquid surface = [6*(19/24)]ft = 4.75ft
ρ is the density of liquid = 64.4 lb/ft³
h is the height of the liquid = 19 ft
Mass of liquid in the cone = ¹/₃ × π × (4.75)² × 19 × 64.4 = 28,914.229 lbs
Part (i) work required to pump the contents to the rim
Work required = 28,914.229 lbs × 9.75 ft = 281,913.733 lb.ft
Part (ii) work required to pump the liquid to a level of 5 ft above the cone's rim
Extra work required = 28,914.229 lb × 5ft = 144571.145 lb.ft
Total work required = (281,913.733 + 144571.145) lb.ft
= 426,484.878 lb.ft
