Answer:the advantage is that he discover many element unknown that time
And the disadvantage is wrong order of atomic masses and the position of isotopes
Explanation:
Answer:
Disadvantage: the isotopes and no separate position also as they have different atomic mass but same atomic number. Since the change in atomic mass of two successive elements was not constant therefore it was difficult to predict the number of missing elements with the help of atomic number only.
It could predict the existence of other elements and could predict their properties so, as to leave space in the periodic table. It could accommodate all the sixty elements discovered at that time and could accommodate the noble gases which, where discovered later.
Tick the statement which is not correct ( a) When a beam of light is passed through a colloidal solution, the path of light gets illuminated ( b ) when an electric current is passed through a colloidal solution , colloidal particles move towards the oppositely charged electrodes. ( c ) when an electric current is passed through a suspension , particles move towards the oppositely charged electrodes. ( d ) when an electric current is passed through an electrolyte solution , particles move towards the oppositely charged electrodes.
Answer:
option a is not correct
Burets are often used to carefully measure the amount of liquid added to a reaction. The long thin buret tube is marked every milliliter and every tenth of a milliliter. Which of the following measurements is correct for a volume of liquid in a buret?
a. 30 ml
b. 32 mL
c. 32.0 mL
d. 32.01 mL
Answer:
c. 32.0 mL
Explanation:
Buret can measure upto one tenth of a mL . That means it can measure upto one decimal point of a mL . Out of given measurement 32.0 mL reads upto one decimal point of mL so this reading seems to be the reading taken of a liquid in a buret.
please am confused and need help
Answer:
1. C
2. C
3. A
4. C
5. True
6. C
Explanation:
1. C The answer is conduction because the heat was transferred through direct contact.
2. C The answer convection because the heat was transferred through a medium (liquid/gas).
3. A The answer is conduction because the heat was transferred through direct contact.
4. C The answer is radiation because the heat was transferred through thermal emission.
5. True. This is because the air that is warmed rises, causing the cool air to replace it. You can picture it like the scenario in question 2.
6. C
state two things you notice about a metal when being touched
Answer: one thing you may notice when you touch metal is a small electric shock, and depending on the temperature, it could be hot, or cold.
who was the 33rd president of the United States?
Answer:
Harry S. Truman
Explanation:
Because he was the 33rd president
♡
Which of the following is not true about
both scientific laws and scientific
theories?
Both are based on hypotheses
Both can be used to make predictions
Both are used to explain why a phenomenon
happens
Both can be modified if new evidence arises
Your question has been heard loud and clear.
Both scientific laws and scientific theories are not based on hypothesis.
Because , scientific laws are proven and so they are real not hypothetical.
Whereas scientifc theories can be hypothetical.
Thank you
Does covalency fail in explaining the formation of BeCl2 and PCl5? Explain
Answer:
Yes , covalency fails to explain the formation of BeCl₂ and PCl₅.
Explanation:
covalent bonds are formed between two atoms by sharing of outermost electrons in order to attain octet for attaining stability . To octet means to attain 8 electrons in their outermost orbit .
BeCl₂ :
Be has two electrons in its outermost orbit and each of Cl has 7 electrons .
Each of Cl shares one electron each with each of two electrons of Be . Cl atoms attain 8 electrons as octet . But Be attains only 4 electrons ( 2 of Be and 2 from Cl atoms ) . Hence octet of Be is not attained . So covalency fails in the formation of BeCl₂ .
PCl₅ :
P has 5 electrons in the outermost orbit . Each of these electrons shares with one electron from each of Cl atoms . Thus Cl attains octel state ( 8 electrons ) but P attains 10 electrons ( 5 + 5 ) , 5 of P and 5 from 5 Cl atoms .
Hence Octet of P is not attained . Hence covalency fails in the formation of PCl₅ .
What is the effect of raising the temperature on the reaction rate? Using collision theory explains why this result was observed.
Answer:
An increase in temperature will result in increase in the average kinetic energy of the reacting particles(atoms). Which will therefore increase the frequency of their collision....
Using collision theory
The reaction rate increases......
Express this number in scientific notation 50000
Answer:
We write 50,000 in scientific notation,
it is written as 5 x 10⁴.
Hope it helps.
Answer: 5×10^4
Explanation:
scientific notation: a×10^b, where should be 0<a<10
Step 1. Count the zeros
There are in total 4 zeros in 50000, so we write the exponent as 10^4
Step 2. Look at the number left
The number left is 5, which technically should be the [a] in the expression. But first, we need to check whether or not is it in the proper range of [a].
0<5<10, is it true? YES
So the final expression should be 5×10^4
Hope this helps!! :)
Please let me know if you have any question
Suppose three different compounds composed of only nitrogen and oxygen were analyzed and the following data were obtained:
Mass of: Samples N O
Compound-A 1.500 g 0.955 g 0.545 g
Compound-B 2.000 g 0.933 g 1.067 g
Compound-C 3.000 g 0.913 g 2.087 g ———————————————————————————
a) Show that this data is consistent with the law of multiple proportions.
(b) If compound-B has the formula NO, what are the formulas of compounds A and C?
Answer:
I think it is b
Explanation:
but I'm not for sure that the answer is right
Which of the following regulates food labels? HACCP FSIS FDA EPA
Answer:
FDA
Explanation:
Answer:
FDA
Explanation: it right ;)
5.22x10-^3 = [? ]x 10-2
Answer:
5.22 x 10^-5
Explanation:
5.22 x 10^-3 x 10^-2 = 5.22 x 10^-5
Use the periodic table to determine whether the compound is a molecule or a formula unit
What is the formula unit we are looking at?
This answer is incomplete plz edit it.
THX
FeS+O2=Fe2O3+SO2????
FeS+O2=Fe2O3+SO2
Iron (II) sulfide + Oxygen gas
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If the yellow car travels from -70 m to 20 m in 5 seconds, what is its velocity?
Answer:
18 m/s
Explanation:
v = d/t = 90/5=18
What is the atomic number of an atom with 20 protons 18 electrons and 22 neutrons
Answer:
20
Explanation:
The atomic number is just the number of protons in an atom. So if the atom has 20 protons, the atomic number is also 20.
what does alternate form mean
Answer:
different versions of existing forms
Explanation:
What is the role of critical thinking in scientific process
Answer:
Critical thinking initiates the act of hypothesis.
Critital thinking initiates the hypothesis. By thinking you will come across a question you want to answer. In the conculsion crititcal thinking is used again to validate the hypothesis.
Why is it necessary to research your experiment before starting it?
Answer: by researching the experiment, it helps you make sure you get everything right. If you didn't research it, there's a possibility you can get the experiment wrong.
The pressure of 10.0 L of gas increases from 1.50 atm to 1240 mmHg. What is the final volume of the gas, assuming constant temperature?
Answer:
The final volume of gas is 9.19 L.
Explanation:
Given that,
Volume = 10.0 L
Initial pressure = 1.50 atm
Final pressure = 1240 mmHg
We need to calculate the final volume of gas
Using formula of ideal gas
[tex]P_{1}V_{1}=P_{2}V_{2}[/tex]
[tex]V_{2}=\dfrac{P_{1}V_{1}}{P_{2}}[/tex]
Where, P₁ = initial pressure
P₂ = final pressure
V₁ = initial volume
Put the value into the formula
[tex]V_{2}=\dfrac{1.50\times10\times760}{1240}[/tex]
[tex]V_{2}=9.19\ L[/tex]
Hence, The final volume of gas is 9.19 L.
Air has a mass of 1.2g and a volume of 4,555ml. What is the density
Answer:
Density = 0.00026 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]Density(\rho) = \frac{mass}{volume} [/tex]From the question
mass of air = 1.2 g
volume = 4,555 mL
Substitute the values into the above formula and solve for the density
That's
[tex]Density = \frac{1.2}{4555} [/tex]= 0.0002634
We have the final answer as
Density = 0.00026 g/mLHope this helps you
Why do you think the "super-hot" Earth's core is important in this
whole process? I need help! For science!!!:)
The "super-hot" earth's core is important because it generates the magnetic field around the earth. it also helps control evolution.
15g is equivalent to how many mg
Answer:
15,000 mg
Explanation:
1 gram=1000 mg
15 gm=15,000 mg
What does one calorie do to water
Answer:
The calorie is a unit of energy widely used in nutrition. For historical reasons, two main definitions of calorie are in wide use. The small calorie or gram calorie (usually denoted cal) is the amount of heat energy needed to raise the temperature of one gram of water by one degree Celsius (or one kelvin). The large calorie, food calorie, or kilocalorie (Cal, calorie or kcal) is the amount of heat needed to cause the same increase in one kilogram of water. Thus, 1 kilocalorie (kcal) = 1000 calories (cal). By convention in food science, the large calorie is commonly called Calorie (with a capital C by some authors to distinguish from the smaller unit). In most countries, labels of industrialized food products are required to indicate the nutritional energy value in (kilo or large) calories per serving or per weight.
Explanation:
Which of the following is the best metaphor for an atom? A. A jigsaw puzzle piece B. A lego block C. A box
Answer:
A box
Explanation:
In quantum mechanics, the atom is metaphorically described as a box. In fact, the Schrödinger wave equation is based on the three dimensional box metaphor of the atom.
Thus, a box provides a convenient treatment of the atom as it represents the fundamental components of the problem of atomic structure, hence the answer.
C. A box
According to Erwin Schrödinger:He proposed the quantum mechanical model of the atom, which treats electrons as matter waves.Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls.For example—is not possible due to quantum effects. Every atom is composed of a nucleus and one or more electrons bound to the nucleus.Thus, the correct option is C.
Learn more:
brainly.com/question/6258301
If you walk 6336 feet, how many miles will you have walked?
Answer:
1.2 miles
Explanation:
Which of the following statements about the nucleus is false? A. Able to be lost or gained in chemical reactions. B. Made up of protons an neutrons. C. None of these D. Contains nearly all of the mass of the atom.
Answer:
A. Able to be lost or gained in chemical reactions.
Explanation:
Only electrons are lost or gained.
Able to be lost or gained in chemical reactions. Hence, option A is correct.
What are atoms?An atom contains a central nucleus surrounded by one or more electrons.
A chemical reaction is not created or destroyed, it simply moves electrons from one atom to another, and does not change the nucleus of the atoms. The total mass of the matter remains conserved in any chemical change.
Hence, option A is correct.
Learn more about atoms here:
brainly.com/question/1566330
#SPJ2
A cation is a metallic ion derived from base.Why is it derived from base?Can you derive it from an acid?
Answer:the cation can't be drived from an acid
Explanation:
Example
HCL+MgOH2=MgCl2+H2O
The cation in the salt magnesium chloride is magnesium which is derived from the base and the anion chlorine from the acid hydrochloric acid. The same is true in water.
Please can you add as brainleist please!!!!!!!!!!!!!!!!!!!!
Describing Matter Matter is anything that has______ and takes up space (_________). The _______________ of an object measures the amount of matter or substance the object contains. Volume is the measure of _________________ by the object.
Answer:
Mass; mass; amount of space taken up.
Explanation:
Matter is anything that has mass and takes up space. The mass of an object measures the amount of matter or substance the object contains.
Volume is the measure of the amount of space taken up by the object.
The SI units for mass and volume are kilogram (kg) and cubic meter (m³) respectively.
Generally, matter exists in three (3) distinct phases and these are;
1. Solid: it is the state of matter in which the physical substance has a definite shape and fixed volume but not compressible. Examples of solids are pen, screwdriver, television, car etc.
2. Liquid: it is the state of matter in which the physical substance can be poured and takes the shape of its container. Also, liquids generally have a definite volume. Examples of liquids are urine, water, milk, blood etc.
3. Gas: it is the state of matter in which the physical substance has no definite shape or volume and as a result fills all available space. Also, gases are easily compressible and can flow. Examples of gases are hydrogen, oxygen, argon, nitrogen etc.
What does the slang term "the Boards" refer to?
Answer:
It can mean "boardwalk" or a "board of a school."
~Mia Sedillo~