B- Mechanical digestion begins in the mouth, and includes the tearing and grinding of food with teeth.
C- Mechanical digestion uses teeth to grind food and saliva to moisten the food
making it easier to chew.
These points are true.
HELP ASAP 10 POINTSSS
In this diagram, the medium on top is air and the medium on bottom is glass. Which vocab word best describes what is happening when the light wave passes from the air into the glass?
Question 2 options:
resolution
diffraction
refraction
reflection
Answer: refraction
Explanation: this is because during refraction light moves from one medium to another.
Which is a definite sign of a chemical reaction?
Chemical properties change.
Physical properties change.
A gas forms.
A solid forms
Answer: here i am choosing two answer because i am not sure . a gas forms and a solid forms
Explanation: a solid forms thus is to say a precipitate is formed
a gas forms thus to say effervescence , fizzing and bubbling whiles a gas is being produced.
A gas has a temperature of 14 °C, and a volume of 4.5 liters. If the temperature is raised to 29
°C and the pressure is not changed, what is the new volume of the gas
The new volume of the gas wii be 4.7 liters.
12. A. 2 g of ferrous sulphate crystals 5 points
are heated in a dry boiling tube. a)
Name and define the type of reaction
that has taken place. b) Write
balanced chemical equation for the
above reaction. c) List two main
observations of this reaction. B. A
shining metal 'M'on burning gives a
dazzling white flame and changes to
a white powder ‘N’. a) Identify ‘M'and
'N'. b) Name the type of reaction
taking place and write the balanced
chemical equation.
Answer:
A) Decomposition reaction.
Decomposition reaction is defined as a chemical reaction whereby a compound is broken down into 2 or more simpler substances.
B) 2FeSO4 + Heat > Fe2O3 + SO2 + SO3
C) - Gas evolution because a gas is part of the product
- Upon heating its colour gradually changes from pale green to reddish brown which implies a change in state
Explanation:
A) Name of the reaction is; Decomposition reaction.
Decomposition reaction is defined as a chemical reaction whereby a compound is broken down into 2 or more simpler substances.
B) The balanced chemical equation is;
2FeSO4 + Heat > Fe2O3 + SO2 + SO3
C) From experience, the 2 main observations of this reaction are;
- Gas evolution because a gas is part of the product
- Upon heating its colour gradually changes from pale green to reddish brown which implies a change in state.
The equilibrium of 2H2O(g) 2H2(g) + O2(g) at 2,000 K has a Keq value of 5.31 x 10-10. What is the Keq expression for this system?
A) [H2}^2[O2} / [H2O]^2
B) [H2][O2] / [H2O]
C) [H2O]^2 / [H2]^2[O2]
D) [H2O]^2 / [H2][O2]
Answer:
B
Explanation:
I don't know how to explain this but you get it
What is natural gas and how does it work
Answer:
Natural Gas is a fossil energy source that formed deep beneath the Earth's surface. It is used in power plants to generate electricity by burning natural gas as their fuel.
Explanation: I hope this helped :)
Answer:
A molecule of natural gas is made up of carbon and hydrogen. When the hydrogen is segregated from the carbon and filled into a fuel cell, it fuses with oxygen to produce water, electricity, and heat. The carbon is released as carbon dioxide in smaller quantities than from gas turbines.
Explanation:
This is the site I got the info from :
How Natural Gas Works | Peak Oilhttps://www.peakoil.net › non-renewable › how-natural-g
Which is an example of cooperation?
individual ants together make up an ants’ nest
when an organism is more successful at hunting than another
when an organism finds a new way to get itself water
when people get together to stop the killing of the hawks, skunks, and weasels
what is the molarity of a solution prepared dissolving 317 g of CaCl2 into enough water to make 2.50 L of solution?
Answer:
1.14 M
Explanation:
Step 1: Calculate the moles corresponding to 317 g of calcium chloride (solute)
The molar mass of calcium chloride is 110.98 g/mol.
317 g CaCl₂ × 1 mol CaCl₂/110.98 g CaCl₂ = 2.86 mol CaCl₂
Step 2: Calculate the molarity of the solution
Molarity is equal to the moles of solute divided by the liters of solution.
M = moles of solute / liters of solution
M = 2.86 mol / 2.50 L = 1.14 mol/L = 1.14 M
Can someone help me with these answers please I’ll give Brainly !!!!
1.What's the first thought that comes to mind when you hear "nuclear"? nuclear, that's the word. well the first thing that comes into everyone's mind in nuclear and they have to think it then think of words that associate with it.
2.the most important point of something.
3.test site
4.
Describe how the Sun and Earth formed.
Answer:
When the solar system settled into its current layout about 4.5 billion years ago, Earth formed when gravity pulled swirling gas and dust in to become the third planet from the Sun. Like its fellow terrestrial planets, Earth has a central core, a rocky mantle and a solid crust.
What is the name of this hydrocarbon?
Answer:
2,3-dimetylpentane
Explanation:
.....................
Alguien sabe como puedo saber si la bebida (gaseosa) al contener agua carbonatada, ¿esta pasa por electrolisi?, ya que el H2O, podria ser que puede ser de reaccion de sintesis, que seria H2+02------>H20? Seria hidrogeno gaseoso y pxigeno gaseoso formaria el agua carbonatada?, ayuda tengo esta duda >_
Answer:
Por formación de burbujas.
Explicación:
La presencia de burbujas en la superficie de la bebida ayuda a determinar si la bebida tiene gas carbonatado o dióxido de carbono. El gas de dióxido de carbono no se puede mezclar con agua ni disolver en agua normalmente. Se puede agregar mediante alta presión al agua para que cuando se coloquen en condiciones normales, el dióxido de carbono se libere en forma de burbujas. No, el gas hidrógeno y el gas hidrógeno no podrían formar agua carbonatada porque ambos son átomos diferentes. El agua carbonatada tiene gas dióxido de carbono, no gas hidrógeno.
PLEASE HELP ME If a radioactive substance has an initial mass of 50 grams
and its mass halves every 5 years, what is the number of
grams remaining after 20 years?
Answer: [tex]3.125\ g[/tex]
Explanation:
Given
Initial mass [tex]A_o=50\ g[/tex]
half-life is [tex]T_{\frac{1}{2}}=5\ years[/tex]
At any time the left amount is given by
[tex]A=A_o2^{-\dfrac{t}{T_{\frac{1}{2}}}}\\\\\text{Insert the values}\\\\A=50\cdot 2^{-\dfrac{20}{5}}\\\\A=50\cdot 2^{-4}\\\\A=\dfrac{50}{16}\\\\A=3.125\ g[/tex]
Natalia dipped two feathers in oil. Then she dipped one feather in cold water and the other feather in hot water. She swirled both feathers around for 20 seconds, then removed them. Her results are in the table. Cold Water Hot Water Before Oil After Oil After Water Before Oil After Oil After Water Mass 1.2 g 4.5 g 4.2 g 1.2 g 4.4 g 3.5 g She also took a picture of each feather after swirling it in water. two feathers, each with oil and beads of water Was either the cold water or the hot water able to remove the oil? Explain your reasoning.
Answer:
The hot water was better for removing the oil.
Explanation:
You can see that because the mass went down more with the hot water. So, that means that more oil was taken out of the feather with hot water.
Answer:
The mass changed from 1.1grams to 4.5 grams. The appearance is another thing that changed when it got dipped in oil. The feather look like it lost some feathers or the feathers became transparent. The feather just looks soggy and heavier overall. I believe that if Natalia dips the feather covered in oil in cold water, the feather will remain the same. If she were to dip it in hot water, the feather will get rid of the oil mostly. Think about it, in the ocean the water is cold right? So when oil spills in the ocean it will stay there. Hot water is the best to remove the oil from the feather.
Explanation:
Hopefully this will help.
Which of the following processes is not an example of physical weathering?
A. acidification
B. abrasion
C. frost action
D. exfoliation
Answer:
acidification
Answer:
I think its A
Explanation:
Hope this helps: )
2
A chart with the densities of four metals is shown.
Metal
Density (gicm')
Titanium
4.5
Zinc
7.1
Nickel
88
Silver
10.5
Students were given a sample of an unknown metal and told to determine
its density. They measured its mass as 26.4 g and its volume as 3.0 cm?
Use the chart to determine which metal the students were given.
Answer:
mass(m)=26.4g
volume (v)=3.0cm²
we have
density =m/v=26.4/3=8.8g/cm³
since it is equal to density of nickel.
Option C nickel is a required answer.
Answer:
[tex]\huge\boxed{\fcolorbox{green}{yellow}{option \: \: c}}[/tex]
Which statement describes the Richter scale?
It cannot account for fault movement during an earthquake.
It measures large earthquakes far from the seismograph.
It estimates the total energy released from an earthquake.
It increases in magnitude as amount of damage increases.
Answer:
It measures large earthquakes far from the seismograph.
Explanation:
It uses a seismograph to measure earthquakes far from the seismograph where seismic waves are used to determine the magnitude of an earthquake.
Answer: d. It increases in magnitude with an increase in size of seismic waves.
Explanation:
Which of the following is an acid-base neutralization reaction?
A
Mg + 2 HCl → MgCl2 + H2
B
SiCl4 → Si + 2 Cl2
C
AgNO3 + KCl → AgCl + KNO3
D
HCl + KOH → KCl + H2O
Answer:
D
Explanation:
The reaction in which an acid reacts with a base to form salt and water is called acid base reaction.
here, HCL ( strong acid) reacts with KOH (strong base) and KCL (salt) and H2O (water) is formed.
The reaction between HCl and KOH is an example of acid-base neutralization reaction. Thus, the correct option is D.
An acid-base neutralization reaction refers to the reaction between an acid and a base that react to form a corresponding salt and water.
The anion from the acid and the cation from the base combine to form the salt. In this case, chloride ions (Cl⁻) and potassium ions (K⁺) combine to form the salt potassium chloride (KCl).
Salt formation leads to neutralization of the charge in the molecule, and also, the pH of the solution gets neutralized whose extent depends upon the strength of the acid and base used.
The hydrogen ions (H⁺) from the acid and hydroxyl ions (OH⁻) from the base combine to form water.
Learn more about acid-base neutralization in:
https://brainly.com/question/31591186
#SPJ1
When 250 ml of water is added to 35 ml of 0.2 M HCl
15.True or False:
The concentration of a solution can be increased indefinitely by
adding solute
.
What primarily causes the spread of acid rain?
through groundwater and aquifers
through streams and rivers
through the atmosphere
through ocean currents
Answer:
(C) through the atmosphere
Explanation:
How many moles are in a solution with a concentration of 5 M and a volume of 0.25 L?
Answer:
160 mL
Explanation:
Which heat source is most directly connected to the seasons?
Answer:
the solar heat source from the sun is what gives us most of the heat
Explanation:
Scientists, emergency personnel, and the weather service keep a close eye on this potential natural disaster that impacts Florida several times each year. What is this disaster being tracked here?
Answer:
hurricane
Explanation:
How much Pb(NO3)2 would need to be added to 100 mL of water to make a saturated solution at 40°C.
Answer:
70g of Pb(NO3)2 would need to be added
Explanation:
As you can see in the solubility graph of lead nitrate, Pb(NO₃)₂, the solubility of this salt (That is, the maximum amount of the salt that can be dissolved in 100g of the solvent producing a homogeneous solution) is 70g in 100g of water = 70g of the salt in 100mL of water.
A saturated solution is also defined as solubility: The maximum amount of a solute that can be dissolved in a solvent.
That means:
70g of Pb(NO3)2 would need to be added
Deforestation is the act of destroying forests so the land can be used for other purposes. Do you think deforestation increases, decreases, or has no effect on the biodiversity of the forest ecosystem? Explain your answer.
Answer:
deforestation decreases biodiversity of the forest ecosystem
Explanation:
Deforestation has to do with the process of felling trees. This process destroys forest ecosystems. Deforestation is normally carried out for the purpose of development.
An ecosystem is a self supporting unit in which living and non living things interact. The different species of plants and animals found in an ecosystem is called biodiversity.
Since organisms in an ecosystem interact among each other and with their non-living environment, destruction of the trees in the forest ecosystem leads to the loss of certain species present in the ecosystem.
For instance, climbers and animals found on tree tops are normal components of a forest ecosystem. When trees are felled and the forest ecosystem is destroyed across the world, these organisms are threatened. This leads to loss of species or loss of biodiversity.
Answer:
Here’s one possible answer:
Deforestation will likely decrease the biodiversity of the forest ecosystem. It reduces the living space and food sources for some of the organisms. Scarcity of space and food may be a threat to the population of those organisms. Over time, some species may die off, leaving fewer species in the forest.
Explanation:
2C2H6 + 7O2 → __CO2 + 6H2O
What coefficient will need to be placed in the blank in order for the following equation to be correctly balanced?
A.
1
B.
3
C.
4
D.
7
Answer:
From the Combustion formula of Organic Compounds....
Exactly 4 Moles of CO2 would make the equation balanced
So
OPTION C
4MOLES
Which is the correct Lewis dot structure of NH2?
H-N-H
H-N-H
A.
B.
N-H-H
H-N-H
C.
D.
-H-N-H
E.
ОА А
ов. В
C C
OD D
ОЕ Е
Answer:
D
Explanation:
which of the following best describes the use of a non renewable resource?
Answer:
Non-renewable resources, such as coal and oil, are the primary source of power in the world, and they are used to power vehicles, factories, and homes. Although affordable, they can be harmful to the environment and are one of the notable contributors to global warming.
Explanation:
source:cfi
Please help me. I am doing a test and, I don’t know the answer.
Answer:
it's the third one ozone layer depletion