Answer:
washing your hands before the lab
rabbit is one of the sweetest animal on world ....change it into positive degree
Answer:
rabbit is one of the sweet animal
in the world
When an iron nail is ground into powder, its mass ____.
a. stays the same
b. decreases
c. increases
d. cannot be determined
When paper turns yellow-brown upon exposure to sunlight, what type of change is likely taking place?
a. a physical change
b. a chemical change
c. neither a physical change nor a chemical change
d. both a physical change and a chemical change
Explanation:
(a) The mass of an object remains the same always. It is independent of its location. In this case, an iron nail is ground into powder. It means that its mass will remain unchanged. Hence, (a) is the correct option.
(b) Whenever there is a change of color of an object, a chemical reaction occurs. It shows that a reaction happens there. In this problem, a paper turns yellow-brown upon exposure to sunlight. A chemical reaction takes place there. Hence, (b) is the correct option.
1) The mass of any substance remains the same irrespective of the state.
Thus, an iron nail ground into powder should have the same mass unless parts of it got lost during grinding.
2) A paper that turns yellow-brown upon exposure to sunlight is likely undergoing a chemical change. It could be that the light oxidizes the atoms of the paper.
Chemical changes occur when the atoms of a substance combine with another substance to form new products. New products are not formed in physical changes and the original product can be retrieved by physical means.
More on physical and chemical changes can be found here: https://brainly.com/question/1161517?referrer=searchResults
what is a compound x in chemistry?
Answer:
no there is not compound x in chemistry
What lead to the discontinued use of DDT? What were its effects on people? Nature? People- Nature-
a 1 mL pipette delivers a measured volume of .98 mL (calculate the percentage error)
Answer:
2%
Explanation:
.98 is 98% of one and therefore they are missing 2%
Answer:
2%
Explanation:
The answer is 2%.
100-98 is 2.
How to calculate the amount of water needed to dilute a solution?
Answer:
Suppose you must prepare 400 ml of a disinfectant that requires 1:8 dilution from a concentrated stock solution with water. Divide the volume needed by the dilution factor (400 ml / 8 = 50 ml) to determine the unit volume. The dilution is then done as 50 ml concentrated disinfectant + 350 ml
1.0250 - 0.00063 =
O 1.02
1.0243
1.02437
DONE
Answer:1.0243
Explanation: I think that is it
The answer is B aka 1.0250 :)
Which statement accurately describes the chemical symbol of an element?
O The chemical symbol is always a single letter.
O The chemical symbol always starts with the same letter as the name of the element.
O The chemical symbol always begins with a capital letter.
OThe chemical symbol can be shared by more than one element.
Answer:
The chemical symbol always begins with a capital letter.
Explanation:
Answer:
c
Explanation:
The chemical symbol of an element always starts with an chemical letter so here the answer is that the chemical symbol always begins with a capital letter.
It can be seen in the different elements chemical symbol .
For example, Tin is having chemical symbol as Sn while lead is having chemical symbol as Pb.
In both these elements, the chemical symbol starts with a capital letter but none of these have their symbol starts with same letter as their name.
PLS I NEED HELP give me examples of an atom
Answer:
Neon (Ne)
Hydrogen (H)
Argon (Ar)
Iron (Fe)
Calcium (Ca)
Deuterium, an isotope of hydrogen that has one proton and one neutron.
Plutonium (Pu)
F-, a fluorine anion.
Explanation:
I got u
Is copper penny react
reaction with Nitric
acid a
Chemical or physical
Change?
Answer:
The reaction that occurs is a redox reaction. The Copper metal (Cu 0)on the copper pennies is oxidized in concentrated nitric acid to produce Cu2+ ions. Copper is easily oxidized to Cu2+, which is blue in aqueous solutions (water) so you should see the solution turn blue as the copper penny reacts.
Have a nice day ;)(^-^)
Taking into account the definition of chemical and physical change, the reaction of the copper penny with nitric acid is a chemical change.
Physical changePhysical changes are those in which the substances involved are the same before and after the change. That is, a physical change is a transformation in which the nature of matter does not change.
Chemical changeChemical changes are considered to be those in which the substances involved are transformed into totally different ones.
In this way, the initial substances do not exist after the phenomenon has occurred and instead, new substances are formed, different from the initial ones.
That is, a chemical change is a transformation in which the nature of matter varies.
This caseWhen a penny of copper reacts with nitric acid, a redox reaction occurs where the copper metal in the copper pennies is oxidized to produce Cu²⁺ ions, whereas because the nitric acid oxidizes the copper, the nitric acid itself is reduced to nitric oxide (NO). Nitric oxide then reacts with oxygen in the air to produce nitrogen dioxide (NO₂). This can be represented by:
Cu + 4 HNO₃ → Cu²⁺(ac) + 2 NO₃⁻ + 2 NO₂ + 2 H₂O
Finally, the reaction of the copper penny with nitric acid is a chemical change because a redox reaction occurs.
Learn more:
https://brainly.com/question/2684420?referrer=searchResultshttps://brainly.com/question/13339068?referrer=searchResultsIs the copper in a copper wire a homogeneous or heterogeneous mixture
1. The density of a substance is 4.8 g/mL. What is the volume of a
sample that is 19.2 g?
Answer:
d= 4.8g/mL
m= 19.2 g
V=m/d
V= 4 mL
Living sustainably means living on ____—the renewable resources such as plants, animals, soil, clean air, and clean water provided by Earth's natural capital. A. Exponential growth natural income ecosystem services factors of sustainability biodiversity
Answer:
natural income
Explanation:
Living sustainably in the 21st century means coexisting with the nature. In other words, to live sustainably means to meet the needs of the human without affecting or degrading the mother nature.
In the context, living sustainably means to live from the natural income from the nature's gift to us, using their natural resources and not hurting them or exploiting them. They may be resources from the soil, plants, clean air, animals, nature's clean water,etc.
A substance has a density of 3.56 g/mL and a mass of 5668 g. What is the volume?
Answer:
The answer is
1592.13 mLExplanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} [/tex]
From the question
mass of substance = 5668 g
Density = 3.56 g/mL
The volume is
[tex]volume = \frac{5668}{3.56} \\ = 1592.1348314[/tex]
We have the final answer as
1592.13 mLHope this helps you
plastics
shells
aluminum
cans
drift
wood
sea
weed
glass
This chart illustrates the type and number of items collected during a clean up of a
beach. Based on the chart, what approximate percentage of the total items result
from the action of people?
Matter and energy are
OA) similar to work and distance.
OB) interconvertible.
O C) not related to each other.
O D) similar to mass and weight.
tony ate 3/4 of the pizza. mike ate 7/16 of the pizza. how much more did tony eat than mike
Answer:
5/16
Explanation:
make them have a common denominator
3/4 needs to be times by 4
so it's
12/16 then you minus 7/16
the answer is
5/16
Answer: 5/16
Explanation:
Multiply tonys 3/4 by 4 in order to get the same denominator as mike's 7/16. You should get 12/16 since 4x3=12, and now you can subtract the smaller fraction 7/16 from the bigger one 12/16, you should get a difference of 5/16.
give an answer to questions 3 will give you 20 point ASSSAAPP
Answer:
Explanation:
1. It is five valence electrons.
2. It is four valence electrons.
3. It is six valence electrons.
4. It is two valence electrons.
I do hope I helped you! :)
Answer:
1. c
2. b
3. a
4.d
Explanation:
An unknown solid has a mass of 837.21 g. The volume of the solid, determined by water displacement is 37.00 mL. Calculate the density of the solid.
Answer:
The answer is
22.63 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]Density = \frac{mass}{volume} [/tex]
From the question
mass = 837.21 g
volume = 37.00 mL
The density of the substance is
[tex]Density = \frac{837.21}{37} \\ = 22.62729[/tex]
We have the final answer as
22.63 g/mLHope this helps you
I really need help with this before 4:50
Your Uncle Danny just moved into a new apartment and wants to make his famous spaghetti sauce for his new
neighbors. Unfortunately, he hasn't unpacked all of his kitchen utensils. His recipe calls for ' a cup of
oregano, however he can only find a teaspoon to measure out his spices. How many teaspoons of oregano
would be the same as a cup?
Answer:
48 teaspoons
Explanation:
1 cup equals 48 teaspoons.
how does kinetic energy at the bottom of a hill compared to its potential energy at the top
Answer:
Kinetic energy would have to work ten times harder than potential energy.
Explanation:
Let’s say you have a boulder and your asked to push it up the hill it would be difficult right? But lets reverse the situation what if you are asked to roll the boulder down the hill it wouldn’t be much work because the hill is basically doing all the work For you. Hope this Helps:)
Which of the following has a negative charge? A.neutrino B.electron C.alpha particles D.gamma rays
Answer:
B. Electrons
Explanation:
Protons have a positive (+) charge.
Neutrons have a neutral (0) charge.
Electrons have a negative (-) charge.
Alpha Particles is a helium atom.
Gamma Rays are radiation.
Neutrino is Quantum Physics.
Harvey mixes two liquids. Which observation of the new mixture most likely indicates a precipitate is O A. a cloudy appearance OB. a bubble formation OC. a change in color O D. a change in odor
Answer:
A cloudy appearance!!
Explanation:
Hope it helps, just took a quiz.
Answer:
a cloudy appearance
Explanation:
i have big brain
Which event always involves a chemical change A boiling B melting C conducting D burning
Answer:
burning
Explanation:
When a chemical change occurs, the matter is transformed into a new substance. When a substance is burned, it will change into something new. Thus, you know that burning is a chemical change. All the other options are physical properties. The substances may change state, but they will not change identities.
- I took the quiz and got 100%
Hope this helps!
story that explains an example of a scientific method
Answer:
I don't understand you question
If Mr. Murchison is testing out how the light in his classroom affects how sleepy his students get, what should his dependent variable be?
Answer:the dimmer the light is,the more sleepy the students become
Explanation:
Zinc reacts with hydrochloric acid according to the reaction equation Zn(s)+2HCl(aq)⟶ZnCl2(aq)+H2(g) How many milliliters of 6.50 M HCl(aq) are required to react with 8.75 g Zn(s)?
Answer:
41.17
Explanation:
n Zn = mass / m.wt
= 8.75 /(65.4) = 0.1338 mole
n HCL = ( from the balanced equation )
2HCL Zn
2mole → 1 mole
x mole → 0.1338mole
n HCL = .268 mole
M= mole/liter
6.50= 0.268/x
so u have0.04117 liter = 41.17 ml
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 41.17 ml of 6.50 M HCl(aq) are required to react with 8.75 g Zn(s).
What is mole?The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.
Mathematically,
number of moles of zinc= mass / molecular mass
= 8.75 /(65.4) = 0.1338 mole
number of moles of HCl ( from the balanced equation )
2 moles of HCl reacts with one mole of Zn
number of moles of HCl = 2×0.1338 =0.268 mole
Molarity = number of mole of HCl/volume occupied by solution
6.50= 0.268/volume
Volume of HCl = 41.17 ml
Therefore, 41.17 ml of 6.50 M HCl(aq) are required to react with 8.75 g Zn(s).
To know more about mole, here:
https://brainly.com/question/15209553
#SPJ5
A recycling center must find a way to separate all of the aluminum cans from those made of nickel or iron. What would be a reliable, efficient way to separate them?
Answer:
Use a giant magnet to pick up the iron and nickel ones, leaving the aluminum behind.
Explanation:
Stay safe!
help me plz, ASAP . (25 points)
Answer:
what is the question
Explanation:
HELP! WILL GIVE BRAINLY!!!
Density is an intensive physical property because the density of a given substance does not change with the size of the sample. (2 points)
True
False
Answer:
True
Density = mass/volume
Suppose that a block has a mass of 20 g and a volume of 20 cm^3.
Density = 20 g/20 cm^3 = 1 g/cm^3
Now, you cut the block in half. The half-block has a mass of 10 g and a volume of 10 cm^3.
The density of the half-block is
Density = 10 g/10 cm^3 = 1 g/cm^3
The density stays the same, even though the size of the sample has changed.
Explanation:
Answer:
✅True
Explanation:
Density is an intensive physical property because the density of a given substance does not change with the size of the sample.
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