A proposed explanation that is based on observations and that can be tested (but hasn't been tested yet) is known as a(n)
Answer: I think its a hypothesis.
Which kind of investigations never include a hypothesis?
O experimental
O systematic
O descriptive
O comparative
Answer:
the answer is descriptive
Explanation:
descriotive never ever have hypothisis
Dimensional analysis, Plz hell I don’t understand and plz explain
Explanation:
30 lb is 480 ounces
34 mi/second is 54.718 kilometre/ second
455 lb/ gal is 54521.024 grams / litre
50 cl is 500 millilitres
55nm is 5.5 × 10^-6 centimetre
9. How many significant figures are there in the number 0.0001372?
A) 7
B) 3
C) 8
D) 4
E) 0
Answer: D. 4
Explanation:
For numbers with decimal point, we should start counting from the first number that non-zero from the left.
0.0001372
We start counting from 1, since it is the first non-zero number
1, 3, 7, 2
There are in total 4 significant figures
Hope this helps!! :)
Please let me know if you have any question or need further explanation
Is it possible for an object to lose weight but at the same time not lose any
mass?
Answer: NO
Explanation:
When you lose weight, you lose mass. These to are directly linked together
Consider this: weight=mass×gravity
If weight decreases, mass also decreases basing on the expression. Gravity is constant (meaning it will not change because mass or weight changes) so it will not impact the result.
Hope this helps!! :)
Please let me know if you have any question
It is possible for an object to loose weight and not loose mass.
The weight of a body is obtained as W= mg where;
W = weight of the body
m = mass of the body
g = acceleration due to gravity
Since the magnitude of the weight of a body depends on its mass, and acceleration due to gravity it is possible for an object to loose weight and not loose mass.
The value of acceleration due to gravity is not the same at all points in the universe. Hence, if an object is moved to a location where the value of acceleration due to gravity is lower, the object will loose weight but not mass.
The mass of an object is constant and does not change irrespective of the location where it is measured.
Learn more: https://brainly.com/question/13860566
You find an unknown substance, which has a density of 10.0 g/ml, and occupies a volume of 80.0 ml. What is the mass of the unknown?
Answer:
Density=mass / volume.
10= mass /80.
mass=10×80.
=800g
please solve this problem
Answer:
option D is correct
Explanation:
the molecule of nitrogen and ethyne have triple bond in them
N2= N≡N
ethyne =CH≡CH
Given that the density of iron is 11.35 grams per centimeter
cubed, what would be the volume of a 1.1 gram piece of iron?
Answer:
Volume = 0.097 cm³Explanation:
Density of a substance can be found by using the formula
[tex]Density(\rho) = \frac{mass}{volume} [/tex]From the question
Density = 11.35 g/cm³
mass of iron = 1.1 g
To find the volume substitute the values into the above formula and solve for the volume
That's
Making volume the subject we have
[tex]volume = \frac{mass}{Density} [/tex]So we have
[tex]volume = \frac{1.1}{11.35} [/tex]= 0.096916
We have the final answer as
Volume = 0.097 cm³Hope this helps you
2
In order for a space shuttle to be launched from Earth into space, rocket forces must be
A.
kept to zero during the launch.
B. less than the gravitational force.
C. equal to the gravitational force.
D. greater than the gravitational force.
Answer:
D
Explanation:
I think it is D. Think about it- if a human jumps, they are less than the gravitational force. But, if you are greater than the gravitational force, I think you will go into space.
Which of the following liquids is most volatile? Select one: a. cooking oil b. motor oil c. alcohol d. water
Answer:
Alcohol.
Explanation:
It has the lowest boiling point and high vapour pressure.
A 210 gram piece of metal has a volume of 81 cm3. What is the density of this metal?
Question 15 options:
129 g/cm3
2.59 g/cm3
0.39 g/cm3
17,010 g/cm3
291 g/cm3
Answer:
The answer is
[tex]2.59 \: \: g / {cm}^{3} [/tex]Explanation:
The density of an object can be found by using the formula
[tex]Density( \rho) = \frac{mass}{volume} [/tex]From the question
mass of metal = 210 g
volume = 81 cm³
Substitute the values into the above formula and solve for the density
That's
[tex]Density = \frac{210}{81} \\ = \frac{70}{27} [/tex]= 2.592592
We have the final answer as
Density = 2.59 g/cm³Hope this helps you
How many Significant Figures does 105.60 have? *
Answer:
5 significant figures
Explanation:
when a candle burns what form of energy does the chemical energy in the candle change
An element has 7 protons 7 neutrons and 10 electrons what is the mass number
Answer:A B
How many electrons are there in Florine with a -1 charge? 10
What is the total number of nucleons in helium? 4
What is the mass number of an element if it contains 19 protons, 19 electrons, and 20 protons? 39
What is the atomic number of an element with 7 protons, 10 electrons, and 7 neutrons? 7
Explanation: Credit to GOOGLE
Can someone help me plzz
Answer: it’s 8
Explanation:
Area is length x width, so you would multiply the 4 by the 2. Or as it says in the question count the squares inside the rectangle. Most of the time, however, you would multiply length x width.
100 POINTS Which observation indicates that the kinetic-molecular theory has limited use for describing a certain gas? Gas particles are acting like tiny, solid spheres. Gas particles are obeying Newton’s laws of motion. Increasing pressure is reducing the volume of the gas. Increasing collisions of gas molecules will increase energy between them.
Gas particles are acting like tiny, solid spheres according to the question. This is option A
What is the observation?According to the kinetic-molecular theory, gases are made up of atoms or molecules that are always moving randomly and independently from one another. According to the hypothesis, gas particles don't have a strong attraction to one another and take up very little space in relation to the overall volume of the gas.
However, it shows that the gas particles are not operating in accordance with the kinetic-molecular theory's presumptions if they behave like tiny, solid spheres.
Learn more about kinetic theory:https://brainly.com/question/15357425
#SPJ1
I need help will give you fives star
Answer:
2
Explanation:
The maximum amount of electrons in an atom that can share those quantum numbers because of the spin quantum numbers (ms) +1/2 and -1/2.
what is conditional reflexes??
Answer:
Actions that you have trained yourself to perform.
they are obtained by experience. they are not passed from generation. they can be learnt or abolished. Higher center's of brain is responsible for conditional reflexes
Explanation:
example riding a bike, swimming, typing
You are unsure of the volume of a substance, but you know that it has a density of 4 g/ml and a mass of 16 grams. What is its volume?
Answer:
4 mL
Explanation:
Use the density formula, d = m/v
Plug in the density and mass to solve for v:
4 = 16/v
4v = 16
v = 4
So, the volume is 4 mL
Explain how heat as a reactant or product in a chemical reaction makes the change endothermic or exothermic?
✅Chemical reactions often involve changes in energy due to the breaking and formation of bonds. Reactions in which energy is released are exothermic reactions, while those that take in heat energy are endothermic.
IamSugarBee
Answer:
Heat as a reactant makes the change endothermic, while heat as a product makes the change exothermic.
Explanation:
In an endothermic reaction, heat is a reactant, making the endothermic reaction cooler than its surroundings. This can be compared to how an ice cube melting requires heat as a reactant.
In an exothermic reaction, heat is a product, making the exothermic reaction hotter than its surroundings. This is compared to how a fire releases heat into the air as a product.
An object is found to have a mass of 54.3 g. Find the object’s density, if its volume is 47.18 cm3
Answer:
d≈ 1.15 g/cm^3
Explanation:
The density of an object can be found by dividing the mass over the volume.
d= m/v
The mass of the object is 54.3 grams and the volume is 47.18 cubic centimeters.
m= 54.3 g
v= 47.18 cm^3
Substitute the values into the formula.
d= 54.3 g/ 47.18 cm
Divide.
d= 1.150911403136922 g/cm^3
Let’s round to the nearest hundredth. The 0 in the thousandth place tells us to leave the 5 in the hundredth place.
d ≈ 1.15 g/cm^3
The density is about 1.15 grams per cubic centimeter.
Sand is made of tiny pieces of rock that have been worn down by wind and water. Explain why the formation of sand is a physical change.
Answer:
This change is only a physical change because the wind and water do not change the chemical make-up of the rock, the weathering is only changing the size nothing else.
Explanation:
Physical changes happen when objects or substances experience a change that does not alter their chemical constitution.
Because some of the physical characteristics of the rocks change, but their personalities do not. The shreds of rock are ordered as their sizes and shapes change, but their identities and total section endure the same.
Some pure calcium carbonate is made to react completely with 100cm3 Hydrochloric acid of unknown concentration. 120cm3 of carbon dioxide was formed at Room temperature. calculate the number of moles of carbon dioxide formed at room temperature
Answer:
Explanation:
as we know that 1dm3 =1000cm3
therefore x dm3 =120 cm3
1000X =1*120
X dm3 =120/1000=0.12
so 120 cm3 =0.12 dm3
now the number of moles of carbon dioxide at RTP is
moles =given volume(dm3)/standard volume at RTP
moles=0.12dm3/24
moles =5*10^-3
Nitrogen dioxide undergoes thermal decomposition according to the second-order reaction 2 NO2(g) 2 NO(g) + O2(g). When 0.500 M NO2 is allowed to react for 90.0 seconds, its concentration falls to 0.0196 M. What is the half-life of the reaction when [NO2]0 = 0.500 M?
Answer:
half-life is 3.67s
Explanation:
The general law of the second-order reaction is:
[tex]\frac{1}{[A]}=\frac{1}{[A]_0}+kt[/tex]
As after 90.0s, the concentration of NO2 decreases from 0.500M to 0.0196M:
[tex]\frac{1}{[0.0196]}=\frac{1}{[0.500]}+k*90.0s[/tex]
49.02M⁻¹ = K*90.0s
0.5447M⁻¹s⁻¹ = K
Now, half-life, t1/2 is:
[tex]t_{1/2}=\frac{1}{K[A]_0}[/tex]
Half-life is:
t(1/2) = 1 / (0.5447M⁻¹s⁻¹*0.500M)
half-life is 3.67sHow many sif figs does the number 93500 have?
Answer:
The number has 3 significant figures.
Answer:
It has approximatly 3
Explanation:
The Significant figures would be 9, 3 and 5!
Yasir wants to determine if there is a relationship between room color and sleep. Based on his research, Yasir makes an educated guess that people fall asleep more quickly in a room painted blue than in a room painted yellow. He asks several people which color they like better—yellow or blue—and uses their responses to determine if his educated guess was correct. What is missing from Yasir's scientific investigation? A. testable hypothesis based on research B. experiment that tests the hypothesis C. variables to be tested by an experiment D. research on the topic to see what others have learned
Answer:
B). An Experiment that tests the hypothesis.
Explanation:
The element that is missing from Yasir's scientific investigation is 'an experiment which tests a hypothesis.' His experiment does not provide a verifiable statement revealing his proposition or prediction regarding the possible outcome of the experiment which could be verified by using a research or investigation. He rather tests his proposition indirectly by asking 'which color they like better' and using it to make an educated guess. Thus, option B is the correct answer.
3.490 x 10^-3 + 1.100 x 10^-2 in scientific notation
Answer:36
Explanation:
An element is defined in chemistry as
Answer:
In chemistry, an element is a pure substance which cannot be broken down by chemical means, consisting of atoms which have identical numbers of protons in their atomic nuclei. The number of protons in the nucleus is the defining property of an element,
Explain why current flowing indicates the presence of ions
Explanation:
An electron current, the flow of electrons, contributes to an electric current since the electron 'carries' negative electric charge. ... The flow of ions (either positively or negatively charged) also contributes to an electric current in, for example, the electrolyte of an electrochemical cell.
hope it will work well?!
The flow of electric charge across two points is referred to it as an electric current. Electron pairs warm circuits in light lamps and electrical furnaces and generate magnetic fields in motors, inductors, and generators, and further calculation can be defined as follows:
The passage of electrical charges is alluded to as an electric charge. Therefore, an electric current is a characteristic that must be 'carrying' by a charge transfer, not an entity. Since electrons 'carry' negative electrical charges, electrons contribute to an electric current. In the electrolyte of the electrolytic system, for instance, the flow of ions leads to an electric charge. Learn more:brainly.com/question/790768
How to prepare R-SH from R-Cl? Show reaction.
Answer:
Alkylation reaction help in formation of thiol R-SH
Explanation:Say lets take sodium hydrosulfide (NaSH) and alkyl chloride (R-Cl)/ any acid like chloroaceic acid or choloro or potassim acetates.
R-Cl + NaSH --> R-SH + NaCl
Such reactions are seen in the production of paper from wood pulp and in the production of organic compounds like thioglycolic acids (TGA)