Answer:
6
Explanation:
what does the period number on the periodic table tell us?
Answer:
The period number on the Periodic table tells you the total number of orbits that the atom will have. In other words, the period number indicates the number of energy levels (or energy orbit) of an atom. For example, 1st period indicates that these elements possess 1 energy shell (or energy orbit).
Explanation:
why do we need to rinse the mouth before collecting the saliva
¿Cómo se llama el grupo IIA de la tabla periódica?
Answer:
los metales alcalinotérreos: berilio (Be), magnesio (Mg), calcio (Ca), estroncio (Sr), bario (Ba) y radio (Ra).
o simplemente llamado grupo 2A
Explanation:
- How much power does it take to lift a
1,000 N load 10 m in 20 s?
Answer:
"500 Joule/sec" is the right answer.
Explanation:
The given values are:
Force,
F = 1000 N
Velocity,
s = 10 m
Time,
t = 20 s
Now,
The power will be:
= [tex]\frac{Force\times Velocity}{Time}[/tex]
On putting the values, we get
= [tex]\frac{1000\times 10}{20}[/tex]
= [tex]\frac{10000}{20}[/tex]
= [tex]500 \ Joule/sec[/tex]
11
Cr2O3 + 2Al → 2Cr + Al2O3
Chromium is produced by reacting its oxide with aluminum. If 76 g of Cr2O, and 27 g of Al completely react to form 51 g of Al2O3. how many grams of Cr are formed?
Answer:
Deci trebuie sa te aplici cu 2 din3 pe suprafata pamanyului chinez
Explanation:
Deci 1287+2086+2762+7:5
5). At what temperature (K) will 0.854 moles of neon gas occupy 12.3 L at 1.95
atmospheres?
Answer:
338.38 K
Explanation:
Applying,
PV = nRT............... Equation 1
Where P = pressure, V = Volume, R = Temperature, n = number of moles, T = temperature.
Make T the subject of the equation,
T = PV/nR............. Equation 2
From the question,
Given: P = 1.95 atm, V = 12.3 L, n = 0.854 moles
Constant: R = 0.083 L.atm/K.mol
Substitute these values into equation 2
T = (1.95×12.3)/(0.854×0.083)
T = 338.38 K
what do mars, pluto, and Jupiter have in common (science) in 8th grade.
Answer:
they are all planets
Explanation:
-
(11) Deduce the number of dyes in food colouring H.
(iii) Suggest why food colouring F does not move during the experiment.
(iv) Explain which two food colourings contain the dye that is likely to be the most soluble the solvent.
(b) Determine which food colouring contains a dye with R, value closest to 0.67
Show your working.
Answer:
(ii) 1 dye
(iii) Food coloring F is insoluble in the solvent
(iv) 'E' and 'H'
(b) Food colouring G
Explanation:
Paper chromatography principle is based on the rates of migration of chemicals across a sheet of paper which are different and it consists of a stationary phase such as the water in the paper and a mobile phase such as the solvent resulting in the partitioning of the components of the mixture across the paper
The solution components are positioned to start in one place from where they migrate and separate out on the chromatography paper
(ii) The number of components into which the food colouring 'H' separates into = 1
Therefore, the number of dyes in food colouring 'H' = 1 dye
(iii) Food coloring 'F' does not move because it is insoluble in the solvent, which is the mobile phase
(iv) The food colouring that contains the dye that is likely to be most soluble in the solvent are does for which the dyes travel furthest, which are;
Food coloring 'E' and 'H'
(b) Using a similar question solution found on 'tutor my self' website, we have;
The [tex]R_f[/tex] values are given as follows;
[tex]R_f = \dfrac{Distance \ moved \ by \ dye}{Distance \ moved \ by \ solvent}[/tex]
The distance moved by the solvent = 5 units
The distance moved by dyes in food colouring 'E' and 'H' = 4 units
The distance moved by dye in food colouring 'G' = 3.3 units
The distance moved by the second dye in food colouring 'E' = 2.7 units
By inspection, we get;
[tex]R_f[/tex] dye in food colouring 'G' = 3.3/5 = 0.66,
Therefore, the dye with [tex]R_f[/tex] value closest to 0.67 is the dye in food colouring 'G'.
how many atoms are in 4.5 moles of Al?
Explanation:
4.5×6.022×10²³
27.099×10²³
According to Avogadro's number, there are 27.10×10²³ atoms in 4.5 moles of Al.
What is Avogadro's number?Avogadro's number is defined as a proportionality factor which relates number of constituent particles with the amount of substance which is present in the sample.
It has a SI unit of reciprocal mole whose numeric value is expressed in reciprocal mole which is a dimensionless number and is called as Avogadro's constant.It relates the volume of a substance with it's average volume occupied by one of it's particles .
According to the definitions, Avogadro's number depend on determined value of mass of one atom of those elements.It bridges the gap between macroscopic and microscopic world by relating amount of substance with number of particles.
Number of atoms can be calculated using Avogadro's number as follows: mass/molar mass×Avogadro's number.As 1 mole =6.023×10²³ atoms , thus,4.5 moles =4.5×6.023×10²³ = 27.10×10²³ atoms.
Thus, there are 27.10×10²³ atoms in 4.5 moles of Al.
Learn more about Avogadro's number,here:
https://brainly.com/question/11907018
#SPJ2
(hurry pls)Carl plugs in a lamp that has 0.67 of resistance and 8.1 volts running through it. What is the amount of current running through the lamp? C 543 A C 0.08 A C 12.09 A C743 A
Answer:
C)12.09 Ampere
Explanation:
V= IR
Where I= current of the system
R= resistance= 0.67 ohm
V= potential difference=8.1 volts
Substitute the values
8.1= I× 0.67
I= 8.1/0.67
=12.09 Ampere
In the Caribbean countries, general election is usually held every _ years
it is held every 4-5 years
You are given 250 mL of a 12.0 M solution of KNO3. To obtain a 5.0 M, to what volume does the solution need to be diluted to?
600 ml
104.17 mL
0.24 mL
60 mL
Answer:
600 mL
Explanation:
molarity 1 * volume 1 = molarity 2 * volume 2. So this means 12 * 250 = 3000 and divide that by 5 to get 600 mL.
What is the mass number of an element?
17 moles of oxygen is equals to how many grams
17 × ( 2 × 16 ) = 17 × 32 = 544 grams
___________________________
What will the change in temperature be when 90 J are applied to 15 g of gold. (Cgold = 0.126 J/gºC)
Round your answer to the nearest whole number.
°C
E
3
4
5
Next
O
I 17
Answer:
48 °C
Explanation:
q = 90J
m = 15 g
C = 0.126 J/gºC
q = mct
90 = (15)(0.126)t
t = 47.62 °C = 48 °C
Answer:
Explanation:
Formula
E = m * c * Δt
Δt is what you seek.
Givens
E = 90 joules
m = 15 grams
c = 0.126
Solution
90 = 15 * 0.126 * Δt Divide by 15
90/15 = 15/15 * 0.126 * Δt
6 = 0.126 * Δt Divide by 0.126
6/0.126 = Δt
47.619 = Δt
Δt = 48 oC
Which of the following statements about alkynes is incorrect?
Alkynes are unsaturated hydrocarbons.
Alkynes have triple bonds.
Alkynes are saturated hydrocarbons.
Alkynes have carbon atoms.
Answer:
Alkynes are saturated hydrocarbons
Explanation:
Alkynes are groups of hydrocarbons that have the general formula of {Cn H2n - 2}. They have a triple carbon to carbon bond (C≡C) in their structure. Ethyne (HC≡CH) is the first member of the alkyne series.
Alkynes like alkenes are unsaturated hydrocarbons because of their triple and double carbon bonds respectively. Unsaturated hydrocarbons do not have a complete hydrogen atom in their structural composition. Hence, the statement that "Alkynes are saturated hydrocarbons" is FALSE.
Find the hydroxide concentration of a LiOH soultion that has a pOH of 8.65.
[OH] = _____ (round to 2 decimal places)
Answer: i need help
Explanation:
How would you find the density of a can of soda pop?
A. Find the mass of the can of soda pop and then multiply by the number of cubic centimeters in the can
B. Find the mass of the can of soda pop and then divide by the number of cubic centimeters in the can
C. Convert a gallon into cubic centimeters and then divide by the mass of the can of soda pop
D. Convert a gallon into cubic centimeters and then subtract the mass of the can of soda pop
Answer:
it's A.
Explanation:
have uh good day ma :)))))))
What volume of water is needed to make 5.41 M solution with 47.71 moles of HCL?
Answer:
0.113 liters
Explanation:
5.41 M / 47.71 moles = 0.113 liters
Using the example of an ambulance, explain the Doppler Effect. Infer why the doppler effect can or cannot occur in all waves. PLEASE ANSWER ILL PICK BRAINLEIST TO THE FIRST ACTUAL ANSWER
Answer:
When the ambulance is coming towardss you the waves are smushed together and sound higher pitched but then it passes you and when tracveling away the waves are scretched out so the whee whoo sounds lower and that is because of the doppler effect
Four satellites are in orbit around the Earth. The heights of their four orbits
are identical. The masses of the four satellites are given in the table. For
which satellite is the gravitational pull of Earth the strongest?
Potassium hydroxide is partially soluble as shown by the
following reaction:
KOH(s) K+ (aq) + OH(aq)
What is the poH of a 3.32 x 10-5 M KOH solution?
pOH =
Your answer should be rounded to three significant figures. Do not Include
units in your answer.
Answer: 4.48 or 4.47
How many moles of aluminum are in 54 grams
why dil. sulphuric acid cannot be used instead of dil.hcl in lab preparation of carbon dioxide gas?
Answer:
Because Sulphuric acid(H2SO4) is one of the substance which have a very high vigourous reaction if mix with chemicals thats why we take the same sulphuric acid but having lighter effects known to be as Dil.Sulphuric And so it is generally use for precaution while during experimentations Thats why we use it.
Hope it helps
(10 POINTS!!!!!!!!!!!
What environmental change will take place when harmful substances get into the food and water supply of animals or plants?
A Climate change
B Increased predators
C Lack of food
D Pollution
need asap
Answer:
A climate change
Explanation:
the surrounding area would be effected in all ways imaginable, such as change in air, soil, water, plants, animals. and if you eat those said animals those harmful things can transfur into you
Based on information from the periodic table, which statement is true for the
element cobalt?
Answer: (A) a cobalt atom contains 27 protons, and most cobalt atoms contain 32 neutrons.
Explanation: just answered the question and that was the correct answer
Answer: The answer is : A cobalt atom contains 27 protons and MOST neutral cobalt atoms contain 32 electrons
Explanation: I took the test
Which of the following would be the best caption for this image?
A
The Coriolis effect causes convection cells of air to circulate through the atmosphere.
B
The pattern of ocean currents is identical to the pattern of wind currents.
C
Uneven heating of land and water causes winds to blow in different directions during the daytime and night time.
D
There are six bands of global wind currents. These bands of wind currents are caused by convection cells created by the warming and cooling of air.
1. True or False: Fungi are reproduced through the spread of spores.
O True
O False
Answer:
True
Explanation:
Fungi reproduce by spawning absurd amount of spores greatly increasing the survival rate of the fungi.
Answer:
true
Explanation:
An 18.7 g sample of platinum metal increases in temperature from 21.2C to 23.5C
when 5.7 J of heat are added. What is the specific heat of platinum?
Answer:
132.53 J/kg.°C
Explanation:
Applying,
Q = cm(t₂-t₁)................ Equation 1
Where Q = amount of heat, c = specific heat capacity of platinum metal, m = mass of platinum metal, t₁ = initial temperature, t₂ = Final temperature.
Make c the subeject of the equation
c = Q/m(t₂-t₁).............. Equation 2
From the question,
Given: Q = 5.7 J. m = 18.7 g = 0.0187 kg, t₁ = 21.2°C, t₂ = 23.5°C
Substitute these values into equation 2
c = 5.7/[0.0187×(23.5-21.2)]
c = 5.7/0.04301
c = 132.53 J/kg.°C
What is the mass of disulfur pentoxide (S2O5)?
Answer: What is the mass of disulfur pentoxide (S2O5)?
Explanation:144.14g/mol