Answer:
Mass of Cr= 78 g
Explanation:
Given data:
Specific heat of Cr = 0.448 j/g.°C
Initial temperature of Cr lump = 89.5°C
Mass of water = 75.2 mL or 75.2 g
Initial temperature of water = 20.5°C
Final temperature of water = 27.4°C
Mass of Cr = ?
Solution:
when we placed the lump of Cr metal into water heat lost by limp is equal to the heat gain by water.
Specific heat capacity of water is 4.184 j/g.°C
Q = mcΔT
Q = 75.2 g× 4.184 j/g.°C × (27.4°C - 20.5°C)
Q = 2171 J
Heat lost by Cr lump is -2171 J. Now we will calculate the mass of Cr.
Q = mcΔT
-2171 J = m ×0.448 j/g.°C × ( 27.4°C- 89.5°C)
-2171 J = m × -27.821 j/g
m = -2171 J/-27.821 j/g
m = 78 g
what is ch2cl2 bond angle?
Answer:
109.5
Explanation:
It's a tetrahedreal with four bonds
Express 14.80 × 12.10 × 5.05 in scientific notation with the proper significant figures.
What is the definition of a transverse wave and what does it look like?
Answer:
transverse waves, motion in which all points on a wave oscillate along paths at right angles to the direction of the wave's advance.
apples cost $1.75 per pound
What conversion factor could be used to determine how many pounds of apples could be bought for $10.00 ?
Answer: my opinion is about 5 pounds of apples that you can get with $10
Explanation:
srry if im wrong
Which example illustrates public scientific communication?
O A scientist collaborates with other scientists to plan an experiment.
O Ascientist sends a preview copy of a journal article to some colleagues.
O A federal government agency holds a press conference to describe the response to and the dangers of a new virus
epidemic,
A federal government agency publishes an article in a professional scientific journal detailing technical details of a
new virus
Answer:
D. A federal government agency publishes an article in a professional scientific journal detailing technical details of a new virus.
Explanation:
Public scientific communication is a way used by scientists to make the audience able to understand the basics of science to communicate an informed decision. There are several skills under public scientific communication that include connect with the public, talk to journalists, make science understandable, and understand the audience.
The best way to connect with the audience is to publish an article in a professional scientific journal because mostly journals are peer-reviewed having standard of quality.
A federal government agency informing about a new virus through an article in a professional scientific journal is the best way of public scientific communication as it will be for a specific audience along with a standard of quality.
Hence, the correct answer is "D".
HELP PLEASE
The production of a_____
is evidence that a chemical reaction has occured. This occurs when a solid is formed by the reaction.
Answer:
Precipitate
Explanation:
Precipitate is defined as the creation of a solid from a solution. When the reaction occurs in a liquid solution, the solid formed is called the 'precipitate'.
A mixture cannot be reversed back to it’s original properties (true or false)
Answer:
False
Explanation:
A mixture is composed of two or more substances that are combined through physical means. It has NOT undergo any changes in its chemical properties. So, even though its appearance change, it can be reverted back.
Answer:
That answer would be false.
Explanation:
Depending on the type of mixture, you can separate it and reverse it back to its original properties through filtration, evaporation, distillation, and chromatography.
Rank the three elements according to their electronegativity,
from highest to lowest:
Fluorine (F), Silicon (Si), Chlorine (CI)
Answer:
F, Si, Cl
Explanation:
The flow of the electronegativity is up and far left. Therefore, the highest amount is in the far left and up because that is the trend. You can look up a graph on google showing the trend.
The Following do not need sun's energy EXCEPT
a. rotating clock
b. evening torch
c. plowing man
d. winding stairways
When comparing bromine to chlorine, bromine has
A. Fewer protons in its nucleus.
B. A weaker effective nuclear charge
C. More valence electrons
D. More electron shielding
Explanation:
I'm pretty sure the answer is D
what is the name of CCI3
carbon trichlorine????
Carbon tetrachloride, also known by many other names (such as tetrachloromethane, also recognised by the IUPAC, carbon tet in the cleaning industry, Halon-104 in firefighting, and Refrigerant-10 in HVACR) is an organic compound with the chemical formula CCl4.
A sample contain 33.42g of metal pellets are poured on to a graduated cylinder initially containing 12.7ml of water, causing the water level to rise to 21.6ml. Calculate the density of the metal
Answer:
3. 76 g/ml^3
Explanation:
We are given the mass of the metal pellets which is 33.4 grams. To calculate the density of the metal, we need to divide the mass by the volume. The volume of the metal is not directly given so we need to find it ourselves. The water was initially 12.7 ml and then it rose to 21.6 ml after placing the metal pellets. This indicate that the volume of the metal pellets is 8.9 ml.
[tex]21.6 - 12.7 = 8.9[/tex]
We can now use the density formula.
[tex]p = \frac{m}{v} [/tex]
[tex]p = \frac{33.42}{8.9} [/tex]
[tex]p = 3.76[/tex]
The density of the metal is equal to 3.76 g/ml.
What is the density?The density of an object can be defined as the mass per unit volume. The average density is equal to the total mass of the object divided by the total volume of the object.
The mathematical formula for the density of the material is expressed as follows:
Density = Mass/Volume
The S.I. unit of the density is Kg/m³ and is an intrinsic property as it is independent of the size. If the size increases, the mass increases as well but the density of the material remains constant.
Given the mass of the metal, m = 33.42 g
Volume of the metal = Volume of water level with metal - volume of water
V = 21.6 -12.7 = 8.9 ml
The density of metal = 33.42/8.9 = 3.76 g/ml
Therefore, the density of the metal is 3.76 g/ml
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How many atoms are in this formula? 2Fe
Answer:
two
Explanation:
There are two atoms in 2 Fe, more correctly written as 2Fe or Fe2. Both atoms are from the same element, iron.
Answer:
2
Explanation:
There are two atoms of the same element in 2Fe.
Hope this helps! :)
Pioneer species like Lichens and Mosses inhabit an area after a major disturbance, such as a volcanic eruption. Over time, other species are found in the disturbed areas, and the number of pioneer species decreases. Why does the number of pioneer species get less?
Answer:
The number of pioneer species get less as the area has more soil to support complex plants and the competition decreases the role of pioneer species.
Explanation:
Pioneer species like Lichens and Mosses inhabit an area after a major disturbance, such as a volcanic eruption. However, with time the number of pioneer species decreases.
The number of pioneer species get less as the area has more soil to support complex plants and the competition decreases the role of pioneer species.
A paint bucket is cheaper than a zinc (galvanized) iron bucket. Which bucket would you buy as a science learning student? Give reasons.
Urgent!!!!!
Answer:
[tex]zinc \: (galvanized) \: iron \: bucket.[/tex]
science 10 workbook
Answer:
for more details are in the pic
Which phrase is most similar in meaning to “scientific theory”?
A. a best guess explanation
B. a rigorously tested explanation
C. an opinion of what should happen
D. a mathematical relationship
Answer:
c
Explanation:
Answer:
A. a best guess explanation
Explanation:
A scientific theory explains why something behaves the way it does and is usually backed up by different sources. They are not speculations and can be proven. Those which are speculations and are not proven are called hypothesis. A scientific theory can also be replaced, if it is found that it does not produce valid results, or if a better theory is proposed which is made of one or more old theories.
Elements found on the right side of the periodic table are considered ___________.
none of these
nonmetals
metalloids
metals
Answer:
nonmetals
Explanation:
Enter the symbol of the element which would have 36 electrons and -3 charge.
Answer:
Arsenic if I understood correctly
Explanation:
Ions can be made by single element or covalently bonded group of elements. The covalently bonded group of elements is called polyatomic ions or polyatomic atoms. Therefore, the element with atomic number 33 and -3 charge is Arsenic.
What is Ions?Any species that contain charge whether it is positive charge or negative charge is called ions. The example of polyatomic ions are sulfate, phosphate, nitrate etc.
Cation is the species that loose electron and attain positive charge while anion is a species which gain electron and attains negative charge so when anion and cation combine in fixed ration the the overall charge of the molecule is zero that is molecule is neutral, the charge over cation and anion is also called oxidation state. The element with atomic number 33 and -3 charge is Arsenic.
Therefore, the element with atomic number 33 and -3 charge is Arsenic.
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why is lithium used in the body?
Answer:
11
Explanation:
3. Which of the following does not affect the solubility of solid solutes?
a. Volume of solvent
b. Stirring
c. Temperature
d. Amount of solvent
Answer:
Temperature
Explanation:
i GUESS that's the ans lol sry I needed points
How does the valence electron configuration (entire last energy level configuration) relate to the group number on the Periodic Table? Use the shorthand notation in your discussion.
Answer:
The valence electron configuration determines the group to which an element belongs to.
Explanation:
The valence electron configuration of an atom of an element refers to the number of electrons in that atoms outermost shell.
The valence electron configuration is related to the group number of an element in that the number of electrons in the valence shell of an atom of an element determines the group to which an element belongs to. For example, all elements having one valence electron belong to group IA of the periodic table. Similarly, all elements having seven valence electrons belong to group VIIA of the periodic table.
This is because, since the reactivity of an element is related to its ability to either gain or lose a certain number of electrons in its valence shell, elements having same number of valence electrons have similar chemical properties.
is the volume of a coffee cup closer to 300 cm cubed or 300 dm cubed
Answer:
It is closer to 300 cm cubed
Explanation:
The volume of a coffee cup is closer to 300 cm cubed because their american volumes are around 10 ounces, and 10 ounces equals about 300 cm cubed. Hope it helps!
Which is one factor that scientists use to classify orders of soil?
A. fertility
B. climate
C.dryness
D.bedrock
Answer: Its B/Climate
Im pretty sure if its wrong srry!
Hope this helped!
Explanation:
Apart from different ways to classify soils. The one factor that scientists use to classify orders of soil is climate. Hence, Option (B) is correct
What is Climate ?Climate is the long-term pattern of weather in a particular area.
Weather can change from hour-to-hour, day-to-day, month-to-month or even year-to-year.
A region's weather patterns, usually tracked for at least 30 years, are considered its climate.
Other factors people uses in classifying orders of soil are;
ClimatePlant typeSoil compositionSoil orders are known as the single dominant attributes affecting soils in any location.
They can be the prevalent vegetation such as Alfisols and Mollisols or the type of parent material such as Andisols and Vertisols or the climate variables such as lack of precipitation etc.
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An object has 15 grams of atoms and displaces 2.5 mL of water when dropped into a cylinder. What is the objects density... HELP IM IN CLASS RN AND I NEED ANSWERS ASAP, grades are due in couple hours
Answer:
6g/mL
Explanation:
The density, which is the mass per unit volume of an object, can be calculated using the formula;
D= m/v
Where; D = density (g/mL)
M = mass of substance (g)
V = volume (mL)
In this question, the object's mass = 15g, volume of water= 2.5 mL, d =?
Therefore,
Density = 15/2.5
Density = 6 g/mL
The object's density is 6g/mL
What would happen if the earth did not have gravity?
Answer:
Explanation:
If the Earth's gravity is lost, all items held to the Earth's surface by gravity would float away. That includes the atmosphere, water, people, cars and animals. If an object were secured strongly to the Earth, it would probably remain attached
Answer:
Everything would be floating
All of the following are examples of making physical changes EXCEPT:
A:painting walls
b:Making ice cubes
C:Making oxygen out of water
D:chopping wood
How many electron shells are in period 1
Answer:
1
Explanation:
The amount of electron shells is the number of the period
after eating an apple and levaing it on top of the table. what will happend to the color of the inner part of the apple? what makes the color of the apple change
Answer:
Answer Below
Explanation:
When you leave an apple on a table outside it will turn brown. This happens because when you cut an apple, you are exposing it's insides to the oxygen in the air. This causes the PPO (polyphenol oxidase) enzyme in the apple's flesh to oxidize the polyphenols, turning them into some other brown colored products. Hence, the color change.
Answer:
brown i can't explain because its a matter of the atoms in the apple mixing with the air and apple is made with nitrogen
Which group of atomic models is listed in historical order from the earliest to the most recent?
The historical order of atomic models from the earliest to the most recent is as: Hard sphere model, electron shell model, and wave mechanical model. Therefore, option (A) is correct.
What is the atomic model?The atomic model can be described as the model used to describe the structure and composition of the atom. The atom as a primary component of matter has been under extensive study to understand the universe.
In the classical model of an atom, the atom is made of smaller particles with an electrical charge called electrons, protons, and neutrons. To understand the atomic models, it is important to understand how these particles make up the atom.
There are five principal atomic models that have been proposed over time, which are Dalton’s atomic model, Thomson’s atomic model, Rutherford’s atomic model, Bohr’s atomic model, and the quantum atomic model.
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Your question was incomple, most probably the complete question was,
Which group of atomic models is listed in historical order from the earliest to the most recent?
A) Hard sphere model, electron shell model, and wave mechanical model
B) Hard sphere model, wave mechanical model, and electron shell model
C) Electron shell model, Hard sphere model, and wave mechanical model
D) Electron shell model, wave mechanical model, and Hard sphere model