_______ in saliva start the chemical digestion process
Answer:
amylase
Explanation:
litmus is made from plant pigment.
it is red when placed in an acidic solution.
it is blue when placed in an alkaline solution.
it is purple when neutral.
a) what do we call substance that change colour like this?
b) what colour would litmus be in a solution of pH 10?
c) what colour would you expect litmus to be in pure water?
Answer:
For (a): The substances are known as acids and bases.
For (b): The color of the litmus for pH = 10 will be blue.
For (c): The color of the litmus for pure water will be purple.
Explanation:
pH determines the acidity or basicity of a solution. There are three types of solution classified based on the pH:
If pH<7 then the solution is acidic in nature If pH>7 then the solution is basic/alkaline in nature If pH=7 then the solution is neutral in natureLitmus paper is used as an indicator to know the type of solution. There are 2 types of litmus paper:
Red litmus paper: It turns blue when placed in a basic/alkaline solution.Blue litmus paper: It turns red when placed in an acidic solution.(a):
An acid is defined as the chemical species that produces hydrogen ions in the solution while a base is defined as the chemical species that produces hydroxide ions in the solution.
(b):
Given pH value = 10
The solution is basic in nature, thus the color of litmus will be blue.
(c):
Pure water is neutral in nature and has a pH of 7.
Thus, the solution of litmus would be purple.
Please help. Which of these are chemical or physical change?
Answer:
Explanation:
a is a physical change you could put the peices back together
b is a chemical change because you cant unburn wood
c is a chemical change because you cant unbake it
d is a physicl change you could te your time and unmix it
When(NH4)2SO4(aq) and Ba(NO3)2(aq) react
Answer:
1 (NH4)2SO4 + Ba(NO3)2 → NH4NO3 + BaSO4
2 (NH4)2SO4 + Ba(NO3)2 → Ba(SO4) + (NH4)(NO3)
Explanation:
Explain why only one type of seismic wave was recorded at location B. (1 sentence only!)
Answer:
p wave
Explanation:
The P wave is designated the primary preliminary wave because it is the first to arrive at a seismic station after an earthquake. It travels at a speed usually less than 6 kilometers per second in the Earth's crust and jumps to 13 kilometers per second through the core.
Determine the mass of ammonium chloride, NH4CI, required to prepare 0.250 L of a 0.35 M solution of ammonium chloride.
If 25.0 g of iron(III) phosphate reacts with excess sodium sulfate, how many molecules of sodium phosphate can be made?
Answer:
so mucjsuat least amount of soduim is will be 25percent
When this gas is burned what will happen to the surface of this type of star?
how can a match light without a spark
Answer:
Use friction
Explanation:
Friction is the force that stops something in motion. It also heats up something, creating a gravitational heat! A match striked against the lighter will create a flame, because of friction :)
8. What is a compound?
A. a substance in which the atoms of three or more elements are combined together
B. an atom with more electrons than protons
C. a substance in which the atoms of two or more elements are combined together
D an atom with more neutrons than protons
Answer:
c
Explanation:
A light bulb has a resistance of 96.8 Ω. What current flows through the bulb when it is connected to a 120 V source of electrical energy?
Answer:
I = 1.23 A
Explanation:
Given that,
The resistance of the lightbulb, R = 96.8 Ω
Voltage, V = 120 V
We need to find the current flows through the lightbulb. Let the current be I. We can use the ohm's law to find it i.e.
[tex]V=IR\\\\I=\dfrac{V}{R}\\\\I=\dfrac{120}{96.8}\\\\I=1.23\ A[/tex]
So, the current flows through the bulb is 1.23 A.
Add labels for mass extinction and adaptive radiation:
Answer:
Couldn't figure out how to edit the other one to attach the image, but here is it with the labels. Also put the same explanation down below so you don't have to go to the other if you wanted to look at it in conjunction with the image.
Explanation:
Mass extinctions are periods of time where the organisms are essentially wiped out in an extremely brief period of time. You can see how the species just drops off. Adaptive radiation occurs when there is a diversification of a group of organisms as evident by the rise in the number of marine animal groups shown by the bracketed area.
How many moles of helium are needed to fill a balloon to a volume of 6.3 L at 28 °C and 320
mmHg?
Round answer to 0.01 decimals
Answer:
.11 mol
Explanation:
Convert mmHg to atms by dividing by 760. Then multiply 6.3 by the atms and divide by .08206*(273+28) to get mol
Long scratch marks that are left behind as evidence of glaciers are called
A. striations
B. cirques
C. fjords
D. roche moutonnees
Answer:
it is A striations
Explanation:
..........
Answer:
Striation
Explanation:
(01.06 LC)
Which statement is true about the substances present in a mixture?
They always consist of the same element.
They are always in the same state of matter.
They can be separated by physical methods.
They can only be separated by chemical methods.
Answer:
They can be separated by physical methods.
Explanation:
Substances in a mixture are not subjected to anything that may change their chemical structure, so they are physical all throughout the process. Therefore, they can be separated using physical methods.
Answer:
They can be separated by physical methods.
Explanation:
I took the final
What method can be used to separate benzoic acid and potassium carbonate
Answer:
To separate the components, a water wash may be attempted to remove benzoic acid, but benzoic acid is not particularly water-soluble due to its nonpolar aromatic ring, and only small amounts would be extracted into the aqueous layer
The method that can be used to separate Benzoic acid and potassium carbonate is : The application of water wash separation method
Benzoic acid is slightly soluble in cold water but becomes more soluble as the temperature of water is increased. Water wash separation method is a methodology used for the selective removal of unwanted compounds in a mixture.
Separation method based on solubility water wash methodprecipitationThe separation of benzoic acid and potassium carbonate is based on the solubility differences between Benzoic acid and potassium carbonate when dissolved in a solvent ( water ) therefore the water wash separation method is the most effective method.
Hence we can conclude that The method that can be used to separate Benzoic acid and potassium carbonate is : The application of water wash separation method.
Learn more about separation methods : https://brainly.com/question/735172
I need help with this :/
Answer:
Blank 1: 1
Blank 2: 2
Blank 3: 1
Blank 4: 1
Explanation:
Assuming this is to balance the equation, write out the amount of each element you have on the reactants side and on the products side
Reactants Products
Ca 1 Ca 1
C 2 C 2
H 2 H 4
O 1 O 2
Comparing the two, we can see that hydrogen and oxygen have different amounts between reactants and products. Therefore, we need to multiply by some number to get the two equal. If we multiply the reactants by 2 we will get the correct amount in the products. So we put a 2 in front of the H₂O to signify this.
The balanced chemical reaction is
CaC₂ + 2 H₂O --> C₂H₂ + Ca(OH)₂
Consider the titration of 82.0 mL of 0.140 M Ba(OH)2 by 0.560 M HCl. Calculate the pH of the resulting solution after the following volumes of HCl have been added. (a) 0.0 mL WebAssign will check your answer for the correct number of significant figures. 13.447 Correct: Your answer is correct. (b) 15.0 mL WebAssign will check your answer for the correct number of significant figures. 12.25 Incorrect: Your answer is incorrect.
Answer:
a) pH = 13.447
b) pH = 13.176
Explanation:
Ba (OH)₂ is a strong base and ionizes completely in solution to give barium amend hydroxide ions.
The equation of the dissociation of Ba(OH)₂ is given below:
Ba(OH)₂ ----> Ba2+ + 2OH-
1 mole of Ba(OH)₂ produces 2 Moles of OH- ions
a) Before the addition of HCl, i.e.,when 0.00 mL of HCl has been added;
Concentration of hydroxide ions, [OH-] = 0.140 x 2 = 0.a) [OH-] = 0.100 x 2 = 0.280
pOH = -log [OH-]
pOH = -log (0.280)
pOH = 0.553
pH = 14 - 0.553= 13.447
b) pH when 15.0 mL HCl has been added
Moles Ba(OH)₂ = concentration × volume
Volume of Ba(OH)₂ = 82.0 mL = 0.082 L, concentration = 0.140 M
moles of Ba(OH)₂ = 0.082 x 0.140 = 0.01148 moles
moles OH- produced by 0.01148 moles of Ba(OH)₂ = 2 x 0.01148= 0.02296
moles HCl = 0.0150 L x 0.560 = 0.0084
moles of H+ produced by 0.0084 HCl = 0.0084
0.0084 H+ willnreact with 0.0084 moles of OH-
moles OH- left after the reaction = 0.02296 - 0.0084 = 0.01456 moles
total volume of new solution = (82 +15) mL = 97 mL => 0.097 L
Concentration of OH- ions = moles / volume
[OH-] = 0.01456 / 0.097 = 0.1501
pOH = -log [OH-]
pOH = -log (0.150)
pOH = 0.824
pH = 14 - 0.824
pH = 13.176
Can someone help me with this. Thank you
Answer:
Location x is experiencing daytime because it is facing directly to the sun.
Explanation:
From a background understanding of the solar system, the side of the planet facing the sun will be experiencing daytime while the other side of the planet will be experiencing either partial or total darkness depending on the location.
From the diagram given above, we can see clearly that location x is facing the sun and as such, light rays from the sun lightens the location. When this happens, location x will be experiencing daytime.
In conclusion, location x is experiencing daytime because it is facing directly to the sun.
Luisa likes to drink water from a plastic bottle. She knows the bottles were formed from synthetic polymers that were created in a chemical reaction. She also knows that synthetic materials can cause problems. Which statement explains the kind of problem that can develop from using synthetic materials such as plastics?
Complete question: Luisa likes to drink water from a plastic bottle. She knows the bottles were formed from synthetic polymers that were created in a chemical reaction. She also knows that synthetic materials can cause problems. Which statement explains the kind of problem that can develop from using synthetic materials such as plastics?
a) plastics have changed the way people use materials
b) plastics have made the lives of people easier
c) plastics have contributed to more pollution
d) plastics have made more work for people
Answer: The correct statement is plastics have contributed to more pollution. Option C.
Explanation:
Synthetic polymers are commonly called plastics. These are referred to as synthetic materials which can be softened by heat or pressure and then moulded into any desirable shape like the the plastic bottle Luisa drank from.
The raw materials for the manufacture of plastics are readily and cheaply available for the refinement of crude oil through series of chemical reactions. They are made by polymerization of monomers which are derived from petrochemicals.
Although they are used in producing materials used daily, it has contributed to more pollution over the years. POLLUTION is the release of chemicals or substances through man's activities, into the environment which causes harm to both man and the environment.
Plastics have contributed to more pollution because most plastics are non- biodegradable and cannot be broken down by microbial action into simple inorganic forms. Therefore, they cause severe land pollution problems since they are not easily disposable. Also is poses a major problem to the world supply of crude oil as it's limited. This is as a result of heavy dependence on crude oil which provides petrochemicals that is the bulk of the raw materials needed for making plastics.
The H-R diagram is useful in
studying all of these about a star
A.except for its brightness b.location in the sky c.temperature
D.magnitude
Answer:
b.location in the sky (If the question is saying:The H-R diagram is useful in
studying all of these about a star except for)
Explanation:
The theoretical HR diagram plots the temperature of the star vs their luminosity (brightness) and the observational HR diagram plots color of the stars vs the absolute magnitude. Depending on mass, stars will also go through specific evolutionary stages that can be seen through the location of the star on the HR diagram. However, the HR diagram will not have data on the location of the star in the sky.
Evaluate three communication skills that can assist you in sustaining positive relationships
1. Accept and celebrate differences. One of the biggest challenges we experience in relationships is that we are all different. We can perceive the world in many ways. Certainly astumbling block that we come across when we try to build relationships is a desire or an expectation that people will think like we do and, in this way, it is so much easier to create a rapport. We feel more comfortable when we feel that people “get” us and can see our point of view. Life, however, would be very dull if we were all the same and, while we may find it initially easier, the novelty of sameness soon would wear off. So accepting and celebrating that we are all different is a great starting point.
2. Listen effectively. Listening is a crucial skill in boosting another person’s self-esteem, the silent form of flattery that makes people feel supported and valued. Listening and understanding what others communicate to us is the most important part of successful interaction and vice versa.
Active or reflective listening is the single most useful and important listening skill. In active listening, we also are genuinely interested in understanding what the other person is thinking, feeling, wanting, or what the message means, and we are active in checking out our understanding before we respond with our own new message. We restate or paraphrase our understanding of their message and reflect it back to the sender for verification. This verification or feedback process is what distinguishes active listening and makes it effective.
3. Give people your time. Giving time to people is also a huge gift. In a world where time is of the essence and we are trying to fit in more than one lifetime, we don’t always have the time to give to our loved ones, friends, and work colleagues. Technology has somewhat eroded our ability to build real rapport and we attempt to multi-task by texting and talking at the same time.
Being present in the time you give to people is also important, so that, when you are with someone, you are truly with someone and not dwelling in the past or worrying about the future. The connection we make with other people is the verytouchstone of our existence, and devoting time, energy, and effort to developing and building relationships is one of the most valuable life skills.
Consider the reaction.
HCl(aq) + KOH(aq) ⟶ KCl(aq) + H2O(l)
In the reaction shown, HCl is
Answer:
the acid used to neutralize the base in oder to form a salt and water
In a unit circle, ø = pi radians What is the terminal point? A. (1,0) B. (0,-1) C. (0,1) D. (-1,0)
Answer:
(-1,0)
Explanation:
If it takes 25 mL of 0.05 M HCl to neutralize 345 mL of NaOH solution, what is the concentration, M, of the NaOH solution?
Answer:
400ml
Explanation:
How much heat is required to raise the temperature of 250.0 g of mercury by 52 degrees * C with a specific heat of 4.18
To raise the temperature of 250.0 g of mercury by 52°C with a specific heat capacity of 4.18 J/ g°C the heat required is 5.434×10¹ kJ.
What is specific heat capacity ?For a substance, it's specific heat capacity is the amount of energy required to raise the temperature of unit mass of that substance by 1°C.
If, specific heat capacity (c) = 4.18 J/ g°C
Mass of the substance (m) = 250.0 g
Change in temperature (ΔT) = 52°C
Energy (Q) = ?
Then mathematically the relation could be represented as
c = [tex]\frac{Q}{ \ m \ (\Delta\ T )}[/tex]
Therefore, [tex]Q = m\times c \times (\Delta\ T)[/tex]
[tex]Q = 250 \times 4.18 \times 52[/tex]
[tex]Q = 54,340 J\\Q = 5.434 \times 10^1 kJ[/tex]
So, to raise the temperature of 250.0 g of mercury by 52°C with a specific heat capacity of 4.18 J/ g°C the heat required is 5.434×10¹ kJ.
To know more on specific heat capacity, click on
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Which statement describes particles of an ideal gas, based on the kinetic molecular theory?
Answer:
There are 5 steps/rules of the ideal gases based on kinetic theory.
Explanation:
1. Particles in a gas are constant moving in random motion.
2. combined volume of the particles is negligible.
3. particles exert no forces on one another
4. any collisions between the particles are completely elastic
5. the average kinetic energy of particles is proportional to temperature in kelvins.
(I had help explaining steps from Sal Khan. I hope this helps! Have a great day!)
Where is the youngest part of the ocean floor found?
A. along the deep sea trenches
B. where ocean sediments are the thickest
C. near ocean ridges
D. where Earth's magnetic field changes polarity
Answer:
the youngest crust of the ocean floor can be found near the seafloor
Litmus turns
in acidic solutions.
green
yellow
blue
red
Answer:
red
Explanation:
red shows if solution is acidic
2C2H6 + 7O2 ------> 4CO2 + 6H2O
If you are given 10 grams of C2H6 and 10 grams of O2 how many grams of H2O would you produce? Hint: find the limiting reactant. Answer should have 3 decimal places.
Right answer gets brainliest
We convert the masses of our reactants to moles and use the stoichiometric coefficients to determine which one of our reactants will be limiting.
Dividing the mass of each reactant by its molar mass:
(10 g C2H6)(30.069 g/mol) = 0.3326 mol C2H6
(10 g O2)(31.999 g/mol) = 0.3125 mol O2.
Every 2 moles of C2H6 react with 7 moles of O2. So the number of moles of O2 needed to react completely with 0.3326 mol C2H6 would be (0.3326)(7/2) = 1.164 mol O2. That is far more than the number of moles of O2 that we are given: 0.3125 moles. Thus, O2 is our limiting reactant.
Since O2 is the limiting reactant, its quantity will determine how much of each product is formed. We are asked to find the number of grams (the mass) of H2O produced. The molar ratio between H2O and O2 per the balanced equation is 6:7. That is, for every 6 moles of H2O that is produced, 7 moles of O2 is used up (intuitively, then, the number of moles of H2O produced should be less than the number of moles of O2 consumed).
So, the number of moles of H2O produced would be (0.3125 mol O2)(6 mol H2O/7 mol O2) = 0.2679 mol H2O. We multiply by the molar mass of H2O to convert moles to mass: (0.2679 mol H2O)(18.0153 g/mol) = 4.826 g H2O.
Given 10 grams of C2H6 and 10 grams of O2, 4.826 g of H2O are produced.