Answer:
B
Explanation:
a chemical change is where two chemicals come in to create a new chemical
Answer:
A change in a substance with no new substances being formed
Explanation:
you're welcome
how different are the duck leeches offsprings from their parents
Rafiq has heard that continued exposure to light for 10 days can change the colour of some blue dyes used to colour cotton clothing. He decides to test this. He takes a piece of clothing dyed with a blue dye which is suspected to lose colour on such exposure. He cuts the cloth into two pieces.
Which experiment is likely to help him conclude if the dye indeed can change colour?
He should expose, for 10 days-
A. Both pieces under 2 identical lamps.
B. One piece under a lamp; keep the other in darkness.
C. One piece for 5 days and one for 10 days under identical lamps
D. One piece folded and one piece spread out under 2 identical lamps.
Rafiq should expose one piece under the lamp for 10 days while keeping the other in the darkness.
What are the elements in this experiment?In this experiment, it is essential to have a control group and an experimental group.
Control group: This is the population that does not receive a "treatment" or in this case the piece of fabric that is not exposed to light. It is essential to have this element because it works as a reference.Experimental group: This is the population that receives a special "treatment" or in this case the piece of fabric that must be exposed to light to test if there is a color change.Which experiment design is the best for Rafiq?Based on the previous ideas, the best for him is to keep one piece of clothing in the darkness (control group), while exposing the other to the light of the lamp (experimental group).
In this way, he can determine if there is a real change of color by comparing both pieces after 10 days.
Learn more about control group in: https://brainly.com/question/1073731
A gas mixture with a total pressure of 745 mmHg contains each of the following gases at the indicated partial pressures: CO2, 125 mmHg; Ar, 214 mmHg; and O2, 187 mmHg. The mixture also contains helium gas. What is the partial pressure of the helium gas
Answer:
219 mmHg
Explanation:
The partial pressure of a gas refers to the pressure exerted by one of the gases in a mixture of gases.
The total pressure of a gas is the sum of all the partial pressures of all the gases in the mixture.
Since the total pressure = 745 mmHg
The partial pressure of helium is;
745 - (125 + 214 + 187)
Partial Pressure of helium gas= 219 mmHg
which equation represents the process of cellular respiration?
Answer:
C 6 H 12 O 6 + 6 O 2 --> 6 CO 2 + 6 H 2 O + ATP is the complete balanced chemical formula for cellular respiration.
Answer:
C6H12O6 + 6O2 -> 6CO2 + 6H2O + 38ATP
Explanation:
glucose + oxygen gas -> carbon dioxide + water + ATP
How do electrons affect the state of an element?
Answer:
Explanation:
All matter is made up of atoms. ... These shells are actually different energy levels and within the energy levels, the electrons orbit the nucleus of the atom. The ground state of an electron, the energy level it normally occupies, is the state of lowest energy for that electron.
3. (10 Points) Write a double replacement reaction where one of the products is
copper (11) oxide. Include the states of matter for each of the reactants and
products.
Answer:
Up to now, we have presented chemical reactions as a topic, but we have not ... A single-replacement reaction is a chemical reaction in which one element is ... single-replacement reactions will occur between two given reactants. This is ... Use the activity series to predict the products, if any, of each equation.
Explanation:
What physical property can be used to distinguish between a 1 cm cube of copper
and a 1 cm cube of sugar?
Select one:
a size
b. lustre
C. cost
d state
State physical property can be used to distinguish between a 1 cm cube of copper and a 1 cm cube of sugar. Hence, option D is correct.
What is physical property?A property (such as colour, hardness, boiling point) of the matter is not involved in its manifestation of a chemical change.
Physical properties are those general properties you notice most readily about a substance, such as its size, state of matter (solid, liquid, or gas), colour, mass, density and strength.
Values for physical properties can be determined by tests that don't alter the substance being tested.
Hence, state physical property can be used to distinguish between a 1 cm cube of copper and a 1 cm cube of sugar.
Learn more about the physical property here:
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are particles in gas close together
Answer:
Solid particles are close together not gas particles
Plz help I will help give brainliest the last option is 4
why is water considered a pure substance?
a. each water molecule is identical
b. water can be broken down by physical means
c. water molecules are made up of different types of atoms
d. water can be combined with other substances by physical means
heLp
How many moles of helium gas are present in 120 liters of STP
Which science process skill uses numbers to describe objects
Answer: Science process skills include observing qualities, measuring quantities, sorting/classifying, inferring, predicting, experimenting, and communicating.
what happens when a covalent bond vs. an ionic bond is formed?
Explanation:
Ionic bonds form when a nonmetal and a metal exchange electrons, while covalent bonds form when electrons are shared between two nonmetals. ... A covalent bond involves a pair of electrons being shared between atoms. Atoms form covalent bonds in order to reach a more stable state.
Define the term "Potential Energy" in your OWN WORDS.
hope this can help you
you can search on google some stuff like your question
What is the mass of .550 mL of alcohol (density = 82.0 g/mL)
Answer:
1.223 g/ml
Explanation:
Choose all that are correct about the elements in the column highlighted in blue
in the periodic table below (there are FOUR correct answers)
help !!!
Answer:
running a business is the best i have ever done to make a good friend of yours to get to the point where you have a lot to say
A 30 gram ball is at rest. Next, a force pushes the ball to the north for 2.5 seconds and the ball accelerates for a rate of 0,70 m/s/s. How fast is the ball going after the 2.5 seconds of acceleration? For credit, who work in detail
Answer:
1.75m/s or 6.3km/hr
Explanation:
here,
acceleration (a) = 0.7m/s^2
mass (m) = 30g
time (t) = 2.5s
initial velocity (u) = 0m/s
final velocity (v) = ?
now,
v = u + at
or, v = 0 + 0.7 * 2.5
hence, Final velocity (v) = 1.75 m/s
if u want to convert to km/hr
then,
1.75 * 3.6 (we know that 1m/s = 3.6km/hr)
= 6.3km/hr
Question 2 (1 point)
Which state of matter has the lowest density and the highest energy?
Your explanation should include a claim, evidence, and scientific reasoning based on the data provided and the process of photosynthesis.
Answer:
yuh 100% true dude
Explanation:
...............
What causes hot air to rise from the pavement on a hot summer day?
Answer:
During the daytime, when the sunlight hits the land surface, it is absorbed, causing the surface to heat up (think about how hot pavement gets on a sunny, summer day). The hot surface then heats up the air near the surface, causing it to rise
Explanation:
Answer:
When sunlight reaches the ground surface during the day, it is absorbed, allowing the surface to heat up (think about how hot pavement gets on a sunny, summer day). The air near the hot surface is then heated, allowing it to rise.
Explanation:
Draw the Lewis structure for SO2. How
many single bonds, double bonds, triple
bonds, and unshared pairs of electrons are
on the central atom, in that order?
1. 3, 0, 0, 1
2. 2, 1, 0, 0
3. 4, 0, 0, 0
4. 1, 1, 0, 1
5. 0, 0, 1, 1
6. None of these
7. 0, 1, 1, 0
8. 2, 0, 0, 2
9. 0, 2, 0, 0
10. 1, 0, 1, 0
Answer:
It should be 9
Explanation:
That’s how I remember drawing them I took chemistry last year. Tell me if it’s good.
When an atom becomes a negative ion, it
It becomes a positives atom. Since it loses electrons it has more of a positive charge than a normal atom.
PLEASE HELP
Electrical devices have been designed to convert electrical energy to other useful
forms of energy. Choose the device which converts electrical energy to kinetic
energy.
Answer:
B. Fan
Explanation:
The device in the options which converts electrical energy to kinetic
energy is the Fan.
When the fan is plugged to a an electric power source, the electrical energy gets converted to kinetic energy as a result of the movement of the blades in which Kinetic energy is defined as the energy as a result of the motion of a particle or substance.
1.How ls an organism organized from the smallest to largest structure?
O Tisaue, Cell, Organ aystem, Organism, Organ
O Cell, Tisaue, Organ, Organ ayatem, Organism
O Cell, Tisaue, Organ aystem, Organ, Organism
O Cell, Organ, Tiasue, Organ aystem, Organiam
Answer:
Cell, Tissue, Organ, Organ system, Organism
What is the mass of a lead block that has a volume of 30 mL?
O 3.39 grams
O .377 mL
O 265 mL
O 339 grams
Answer:
d
Explanation:
i think it's d, but I'm not sure. my answer is a little different but maybe i used a different number for the density of lead (11.35g/cc)
3. What is the energy of a photon whose frequency is 5.2 x 1015 Hz? Use the equation: E = hxv
h= 6.626 10-34 J xs
4. What is the frequency of radiation whose wavelength is 2.40 x 105 cm? v=c+X
C= 3 x 108m/s
Answer:
3. 3.45×10¯¹⁸ J.
4. 1.25×10¹⁵ Hz.
Explanation:
3. Determination of the energy of the photon.
Frequency (v) = 5.2×10¹⁵ Hz
Planck's constant (h) = 6.626×10¯³⁴ Js
Energy (E) =?
The energy of the photon can be obtained by using the following formula:
E = hv
E = 6.626×10¯³⁴ × 5.2×10¹⁵
E = 3.45×10¯¹⁸ J
Thus, the energy of the photon is 3.45×10¯¹⁸ J
4. Determination of the frequency of the radiation.
Wavelength (λ) = 2.4×10¯⁵ cm
Velocity (c) = 3×10⁸ m/s
Frequency (v) =?
Next, we shall convert 2.4×10¯⁵ cm to metre (m). This can be obtained as follow:
100 cm = 1 m
Therefore,
2.4×10¯⁵ cm = 2.4×10¯⁵ cm × 1 m /100 cm
2.4×10¯⁵ cm = 2.4×10¯⁷ m
Thus, 2.4×10¯⁵ cm is equivalent to 2.4×10¯⁷ m
Finally, we shall determine the frequency of the radiation by using the following formula as illustrated below:
Wavelength (λ) = 2.4×10¯⁷ m
Velocity (c) = 3×10⁸ m/s
Frequency (v) =?
v = c / λ
v = 3×10⁸ / 2.4×10¯⁷
v = 1.25×10¹⁵ Hz
Thus, the frequency of the radiation is 1.25×10¹⁵ Hz.
what are the elements of the following compounds: sodium bromide,zinc sulphide,lead oxide,magnesium nitride,potassium oixide
Sodium , bromine zinc magnesium sulphur nitrogen potassium oxygen lead
How many moles of oxygen are in a sample of 29.1 moles of coal (C135H96O9NS)?
Answer:
2.19moles
Explanation:
mole = mass ÷ molar mass
Molar Mass of the compound, C135H96O9NS =
12(135) + 1(96) + 16(9) + 14 + 32
= 1620 + 96 + 144 + 14 + 32
= 1906g/mol
Next, we calculate the mass percent of Oxygen in the compound
O9 = 16(9) = 144g/mol
144/1906 × 100
= 0.0755 × 100
= 7.55%
This means that there are 0.0755g of Oxygen in 1 mole of the coal compound.
Hence, in 29.1 moles of coal, there would be 29.1 × 0.0755
= 2.19moles of Oxygen
What helps your heart beat? Will give brainlist to whoever answers first!!
Answer:
running helps my heart beat
Answer:
Exercise: The easiest and most effective way to achieve a lasting lower heart rate is to do regular exercise. 2. Stay hydrated: When the body is dehydrated, the heart has to work harder to stabilize blood flow. Throughout the day, drink plenty of sugar- and caffeine-free beverages, such as water and herbal tea.
The overall long-term effects of air pollution are not yet certain.
True
False
Answer:
its true
Explanation:
because I made sure it was true and it is