The question is incomplete, the complete question is;
Theresa creates an experiment where she mixes two red-colored substances together in a container and observes the solution slowly changing from red to blue for the next eight minutes. The solution becomes completely blue after eight minutes. What does this represent about the type of change happening in the container? A chemical change started immediately and finished at eight minutes. A non-chemical change started immediately and finished at eight minutes. A chemical change occurred at four minutes. A non-chemical change occurred at four minutes.
Answer:
A chemical change started immediately and finished at eight minutes.
Explanation:
A chemical change is one in which a new substance is formed. One of the indicators that a chemical change has occurred is the change in the color of the system from red to blue.
The question clearly stated that the change occurred gradually. This means that the reaction must have started immediately the substances were mixed and went on to conclusion after eight minutes when the complete blue color appears.
What are the advantages of using resources such as geothermal energy, solar energy, and hydropower?
They produce large amounts of energy from burning fuels.
They can generate power by burning wastes.
They come from energy sources that never run out.
They increase the amount of greenhouse gasses.
What causes high and low tides?
O A. Variations in salinity and temperature transmit waves across the
ocean.
B. As Earth rotates, the moon's gravity pulls on different parts of the
planet.
C. Ocean water is driven by differences in water density.
D. Underwater disturbances displace large amounts of water.
SUBMIT
what are cons of viruses ?????? oh dont mind this i jus gotta get this out of my head dont stop pop tht pop tht mhm jus like tht mhm shake it shake it mhm work it work it!!!!!!!!!!!
Answer:
Viruses can weaken your immune system. They make you sick. Some could even cause death.
Explanation:
I hope this helped I heard that song I forgot the name lol
How is a "decay event' recorded
______ have trees with cones.
A. temperate rainforests
B. boreal forests
C. tropical rainforests
D. temperate deciduous forests
Answer:
D.
Explanation:
If a disease destroying barley plants in a field swept through an ecosystem, what would happen to the barley eating bird populaiton in the field?
Answer:
It would decrease
Explanation:
In an ecosystem, organisms feed on one another for survival due to the fact that energy needed for metabolic activities in individual organisms can only be obtained via food. This question depicts that certain bird population feeds on barley plant in an ecosystem.
However, If a disease attacks the plants in such a way that it destroys the barley plants in the field, this would cause the barley-eating bird population to DECREASE because their food source has been affected.
Answer:
the barley-eating bird population in the field would decrease.
Explanation:
Determine a skier's velocity in km/h, if it takes her 1.7 min to ski down a
1.67 km slope.
Answer:
103
Explanation:
do not listen to the haters
Which of the following are soluble in water: salt, gravel, or pepper
8. Which type of element requires the least amount of energy to remove an electron?
Answer:
nonmetals
Explanation:
You have 16.6 g of water at 40.2 C. How many Joules are needed to warm the water to 44.8 C?
Answer:
Q = 319.49 J
Explanation:
Given that,
Mass, m = 16.6 g
Initial temperature, [tex]T_i=40.2^{\circ} C[/tex]
We need to find the heat needed to warm the water to 44.8 °C. The formula that is used to find the heat required is given by :
[tex]Q=mc\Delta T\\\\Q=mc(T_f-T_i)\\\\Q=16.6\ g\times 4.184\ J/g^{\circ} C\times (44.8-40.2)^{\circ} C\\\\Q=319.49\ J[/tex]
So, 319.49 J of heat is needed to warm water.
The number of atoms of an element in a chemical formula is given by the _________.
Answer:
Explanation: In a chemical formula, the symbols for each element in the compound are followed by subscripts that tell us how many of that element are in the compound. The subscripts that follow each element's symbol indicate how many of that element are in the compound. Notice how H is located in more than one place.
Explanation:
8. The following system contains 20.0 psi each of gases A and B in the end bulbs with an evacuated bulb in the centre. Both stopcocks are opened at once. What is the new overall pressure in the system?
I literally have no idea how to even start this, I know that the answer is 13.3 psi, but I don't have any clue why or how to get there.
Answer:
13.3
Explanation:
Before opening the stopcocks you have 40psi in total.
After that, those 40psi will be divided into 3bulbs, so 40/3=13.3psi for the system.
Which of the following materials would probably be used as a conductor of electric current in a computer chip?
A rubber
B. glass
c. plastic
D. gold
Answer:
gold is metal which is a very good conductor for electric current and most chips are made out of it.
Answer:
The answer is D. gold
Explanation:
Please help me with my Chemistry homework!! I have so much homework to do for other classes and I’m so stressed so even answering one question would be amazing!!!
1. A graduated cylinder had an initial volume of water of 22 mL. After an iron nail is dropped into the cylinder, the water rises to 38 mL. What is the volume of the nail?
2. Ms.Chavez dropped a gold ring into a graduated cylinder filled with water. The water level was originally at 20 mL. Now the water is at 25mL. Ms.Chavez knows that means the volume of the ring is 5 mL. What else would she have to do to find the density of her ring? Explain.
3. A simple of liquid propanol has a volume of 20.0 cm*^3 and a mass of 15.0 g. What is the density of propanol? Write only your answer below.
What human activity has caused the Increase of CO2 in the atmosphere?
The diagram is a model of one way that materials move into a cell.
Which Sentence explains what happens in last step?
A. a vacuole carries particles into the cell
B. The cell membrane surrounds particles outside the cell.
C. Phospholipids in the cell membrane allow particles to pass through
D. Transport proteins push particles out of cell.
Answer:
B. The cell membrane surrounds particles outside the cell.
Explanation:
The last step is when the cell membrane completely surrounds particles outside the cell.
This process is often known as endocytosis.
endocytosis is the process whereby a cell ingests materials by engulfing them using the cell membrane. In this process, the cell membrane completely covers the food.Which best describes the current model of the atom?
O A a central nucleus containing protons with electrons orbiting in specific paths
O B. a solid sphere unique for everything that exists
O c a solid sphere with electrons and protons embedded
O D. a central nucleus containing protons and neutrons with electrons orbiting in levels of high probability
Explanation:
i think the answer might be D
Atoms and ions are all the same.
Answer:
Yes they are
Explanation:
Boron- 11
Atomic #
Atomic mass
# of protons
# of neutrons
# of electrons
Answer: 5 protons 6 neutrons and 5 electrons. and atomic number is 5.
Hope this helps!
Find the density of a 720.0 g block of Titanium with these dimensions: L = 10.0 cm, W = 8.0 cm, H = 2.0 cm
please someone help me its due today thanks :D
Answer:
D
Explanation:
All of the above are great examples!
"Endothermic reactions are those which absorb heat during the reaction."
The _____________ is similar to a vacumn cleaner because it cleans up cell waste.
a
endoplasmic reticulum
b
lysosome
c
mitochondria
d
cell wall
How do you calculate wavelength and frequency?
Answer:
Wavelength can be calculated using the following formula: wavelength = wave velocity/frequency. Wavelength usually is expressed in units of meters. The symbol for wavelength is the Greek lambda λ, so λ = v/f.
Explanation:
Just a formula that's commonly used in biology.
A 7.0 liter balloon at room temperature contains helium gas. if the temperature is halved, what happen to the volume?
The volume = 6.71 L
Further explanationCharles's Law
When the gas pressure is kept constant, the gas volume is proportional to the temperature
[tex]\tt \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}[/tex]
V₁=7 L
T₁=25 °C(room temperature) + 273 = 298 K
T₂=12.5(halved) + 273 = 285.5 K
[tex]\tt \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}\\\\\dfrac{7}{298}=\dfrac{V_2}{285.5}\\\\V_2=6.71~L[/tex]
A student investigated the time taken for amylase to breakdown a 10% starch solution into glucose at
37°C. The student repeated the investigation five times
Figure 11 shows the results
time taken for amylase to produce glucose (s)
Test 4
120
125
110
115
Figure 11
() Calculate the rate of amylase enzyme activity for the 10% starch solution.
Answer:
Phenolphthalein is an indicator. It is pink in alkaline solutions and turns colourless as the pH decreases.
It can be used to measure the activity of the enzyme lipase on the breakdown of lipids.
Samples of milk containing phenolphthalein were incubated with lipase at different temperatures.
The time taken for the phenolphthalein to turn colourless was recorded and used to calculate the rate of enzyme activity.
Figure 10 shows these results.
Picture
(a) (i) Explain why phenolphthalein turns colourless when lipase breaks down the lipids in milk. (2)
(ii) Describe the effect of temperature on the activity of lipase, as shown in Figure 10. (2)
(iii) Explain why the activity of lipase changes above a temperature of 40°C. (2)
(b) A student investigated the time taken for amylase to breakdown a 10% starch solution into glucose at 37°C. The student repeated the investigation five times.
1 point
What would 140000000.0 be in scientific notation?
a. 1.4 x10-8
b. 1.4 x108
c. 14 x10-7
d. 14 x107
Answer:
B
Explanation:
you're moving the decimal 8 spots to the left so it can only be B
The element with the smallest iconic radius in the alkaline earth metals is
Answer:
Metal.
Explanation:
Metal has the smallest iconic radius in the alkaline earth metal.
Which part of project management involves determining possible risks?
Answer:
Resources
Explanation:
Answer:
Explanation:
M
(?)Li2O + (?)H2O → (?)LiOH
what goes inside the question marks?
Answer:
(1)Li2O + (1)H2O → (2)LiOH
Hope this helps!
pt Which of the following is an example of potential energy?
A. a rolling ball
B. a turning windmill
C. a compressed spring
D. a moving train
Answer:
C . a compressed spring