Which of these substances has a definite volume but not a definite
shape?
A. paper
B. grass
C. juice
D. water vapor
How does Bohr’s model of the atom compare with Thomson’s model?
They both describe atoms as small, indivisible spheres.
They both describe electrons as moving around the nucleus.
They both describe electrons as being surrounded by the positive matter.
They both describe atoms as being made up of positive and negative matter.
Answer: They both describe atoms as being made up of positive and negative matter.
Answer:
They both describe atoms as being made up of positive and negative matter.
Explanation:
I did it on edge
Order the following atoms from smallest to largest atomic radius: C, N, P
Answer:
N, C, P
Explanation:
HELP PLEASE
Which of the following BEST describes
the size of asteroids?
A. All of them are smaller than a kilometer in diameter.
B. All of them are larger than 100 kilometers in diameter.
C. They range from smaller than 1 km to about 300 km in
diameter.
D. They range from 1 km to about 100 km in diameter.
I put chemistry because there’s no astronomy
Answer:
I think B is the answer so hope
Answer:
It's C
Explanation:
11. Which elements are least likely to react with other elements? A) metals C) nonmetals B) noble gases D) transition elements
Answer:
I believe the answer is B. Noble gases.
Explanation:
their outer shell is already full of electrons which makes then less reactive.
How many molecules are found in 60 grams of KOH?
Explain step by step please
Answer:
6.624× 10²³ molecules
Explanation:
Given data:
Mass of KOH = 60 g
Number of molecules = ?
Solution:
First of all we will calculate the number of moles.
Number of moles = mass/molar mass
Number of moles = 60 g/ 56.1 g/mol
Number of moles = 1.1 mol
Now number of molecules are determine by using Avogadro number.
1 mole = 6.022 × 10²³ molecules
1.1 mol × 6.022 × 10²³ molecules / 1mol
6.624× 10²³ molecules
Avogadro number:
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
"Religion and culture are also affected by the climate and topographic diversity."
Justify this statement
Answer:
In a survey of a group of people, it was found that 60 0f them have
business, 45 have government jobs, 125 have farming, 27 have business
only, 15 have government job only, 10 have business and government
job only, 5 have government job and farming only.
i) How many people have all the profession?
ii) How many people were there in a survey?
What does the nucleus of an atom do to its own electrons? To the electrons of a nearby atom?
An alcohol thermometer makes use of alcohol's changing in order to measure temperature. As the temperature goes up.
the alcohol contained in the thermometer increases in volume, filling more of the thermometer's tube.
A. state
B. mass
C. density
D. chemical composition
The question is incomplete, the complete question is;
An alcohol thermometer makes use of alcohol's changing _______ in order to measure temperature. As the temperature goes up, the alcohol contained in the thermometer increases in volume, filling more of the thermometer's tube.
A.
mass
B.
state
C.
chemical composition
D.
density
Answer:
D.
density
Explanation:
Every kind of thermometer makes use of a change in a particular physical property of a substance as a measure of temperature. It must be a property that changes with temperature.
Density of a substance changes with temperature. Even though the mass of alcohol in glass remains constant, but its volume increases or decreases with change in temperature leading to a change in volume and consequently a change in density of the alcohol in glass. This change is used as a measure of the change in temperature.
6. Why does DNA need to be organized into chromosomes before cell division?
The DNA would be too difficult to separate without this organization.
The DNA would take up too little space without this organization.
The DNA would be pulled apart rapidly without this organization.
The DNA would be broken without this organization.
Answer:
The DNA would be too difficult to separate without this organization.
Explanation:
DNA is usually wrapped loosely, but when ready to divide it wraps tighter. It's so each chromosome is a distinct unit. When the cell divides one copy goes to each of the resulting cells. If not lined up properly sereve genetic issues can occur. Chromosome alignment makes the process more efficient.
Which best explains why the atomic theory is a scientific one?
A. The theory was written by a famous scientist and has been around
for a very long time.
B. The theory describes what atoms are and has not changed over
time.
C. The theory explains many observations and is supported by a
large amount of evidence.
D. The theory represents a guess by many different scientists about
how atoms work.
Answer:
C
Explanation:
Answer:
it will option c it is perfect
What are the coefficients when the following equation is correctly balanced? _____ Al + _____O2 ---> _____Al2O3
properties changes if the size of an object changes?
A.mass
B.volume
C.weight
D.all of the above
Answer:
D
Explanation:
The answer should be D, when the size of an object changes it changes how much mass it has how heavy it is (weight), and how much space it takes up (volume).
5. Describe the effects of photons of light on an electron of the hydrogen atom
Answer:
How do atoms give off light?
Atoms emit light when they are heated or excited at high energy levels. The color of light that is emitted by an atom depends on how much energy the electron releases as it moves down different energy levels. ... It shows the electron moving down energy levels.
Explanation:
HELP HELP HELP HELP HELP HELP HELP
Q2. Here is the word equation for a chemical reaction.
magnesium
+
zinc oxide
magnesium oxide
+
zinc
Write down everything that the word equation tells you about the reaction
(Total 4 marks)
Explanation:
magnesium + zinc oxide --> magnesium oxide + zinc
Mg + ZnO --> MgO + Zn
Reactants:
- Magnesium
- Zinc Oxide
Products:
- Magnesium oxide
- Zinc
Type of reaction: Displacement Reaction
The provided word equation depicts a chemical reaction between magnesium and zinc oxide that results in the creation of magnesium oxide and zinc.
Magnesium and zinc oxide are the reactants in the process. These are the substances that alter chemically. The process produces magnesium oxide and zinc. These are the new chemicals produced by the chemical process. This reaction undergoes a chemical transformation, as indicated by the term equation. Magnesium oxide and zinc are formed when magnesium interacts with zinc oxide.
The reaction's stoichiometry is not explicitly stated in the word equation. We cannot establish the exact quantities of the reactants and products involved without further information or factors. The term equation denotes that the reaction obeys the rule of mass conservation. The total mass of reactants must equal the total mass of products.
To know more about word equation, here:
https://brainly.com/question/2602833
#SPJ6
How many moles are in 7.91 X 1022 atoms of He?
Answer:
amount of He = (7.91 × 10^22) ÷ (6.02 × 10^23) = 0.131mol (3sf)
Explanation:
you make use of the mole concept formula
amount(mol) = number of particles ÷ 6.02 × 10^23
(6.02 × 10^23 is the avogadro constant, which is an extremely important number in this formula for mole concept)
A science teacher gave a student a sample of a clear liquid labeled "unknown
substance." Which property would best help the student determine the
sample's identity?
A. The sample's boiling point
B. The sample's mass
C. The sample's volume
D. The sample's weight
Answer:
A. The sample's boiling point
Explanation:
Because by knowing boiling point we easily find a substance for example if given clear liquid boiling point is 100 c° we immediately know this is water.
Moreover boiling point is a fixed quantity for a substance.
What is the answer to question 7, NH4C2H3O2
Answer:
Ammonium acetate was not sure at first but it was Ammonium acetate sorry i was confused at first
Hope this helps :D
Can someone answer all 3 questions plz?
Question one should be obvious..
Mass can't be created not destroyed no matter what, so even in a chemical reaction, the answer will remain. The first answer is correct.
Question two
No, because even when water is broken down, there should only be one molecule of oxygen. The fact there is two means it's incorrect.
Question three
Yes. The equation is perfectly balanced on both sides, so it's safe to say the value of mass remains constant.
please help! 35 points for a valid answer!
how is the potential (voltage) of a redox reaction determined using the reduction potential chart calculate the voltage for the equation in 3(a)
Answer:
Oxidation half reaction is written as follows when using using reduction potential chart
example when using copper it is written as follows
CU2+ +2e- --> c(s) +0.34v
oxidasation is the loos of electron hence copper oxidation potential is as follows
cu (s) --> CU2+ +2e -0.34v
Explanation:
Answer:
The potential difference is caused by the ability of electrons to flow from one half cell to the other. Electrons are able to move between electrodes because the chemical reaction is a redox reaction. ... The cell potential (Ecell) is measured in voltage (V), which allows us to give a certain value to the cell potential.
Explanation:
On any given day or night, what determines the visible phase of the moon
A. how much of the sunlit side of the moon is visible
B. the time of day or night that we look at the moon
C. how far the moon has rotated on its axis
D. how much of the moon is lit by the sun
Answer:
i think the answer is D if not its A
Please help! Due today. Look at the image:
Reuploaded
Answer:
3
Explanation:
2+2=4-1=3 quick maths
please help me, please
Answer: NaCl and H2O
Explanation: Products are on the right side of the arrow :)
Answer:
B. NaCI
D. H2O
Explanation:
The product is the result, which in this case is sodium chloride and water.
Please mark as Brainliest!!!At about what temperature does the sample change phase? Justify your
answer based on the cooling curve shown above.
A student states, “When the alcohol sample was at a temperature of 500 K, all the particles were moving faster than any of the particles were moving at
400 K" Do you agree or disagree with this student's statement? Justify your
answer.
Please help! Which Zeros are significant in the measurement .0506010 kg?
a b c d
.0506010 kg
b,c
a, b, c
b, c, d
a, b,c,d
Pick out the metals which can react with magnesium sulphate solution. Justify the answer.
calcium, aluminium, mercury, sodium, platinum, copper
Answer: aluminium, mercury , platinum and copper.
Explanation:
A single replacement reaction is one in which a more reactive element displaces a less reactive element from its salt solution. Thus one element should be different from another element.
A general single displacement reaction can be represented as :
[tex]XY+Z\rightarrow XZ+Y[/tex]
Thus the metals which are more reactive than magnesium will react with magnesium sulphate solution.
The metals which are more reactive than magnesium are aluminium, mercury , platinum and copper.
What is a part's structure related to?
How many neutrons are in neon?
Answer:
10
Explanation:
What are two types of matter are pure substances
Answer:
Elements and compounds are two types of pure substances.
Explanation: