Answer:
..
Explanation:
why are magnesium fluoride and calcium allowed in water
Answer:
calcium allowed in
Explanation:
Why are magnesium, fluoride, and calcium allowed in water?
✓ They’re naturally occurring elements in many springs & aquifers used for water supply purposes - calcium and magnesium are also essential minerals
MAKE A POSTER OR SLIDES OF THE FOLLOWING INFORMATION
Important Details:
Due Date: October 8, 2021
Maximum group size: 2
Information to Include:
Origin –
ð Date of discovery
ð Discoverer
Background – Use these aspects of your element to describe your superhero (if you can’t think of how to show one of these, you could always use it as decoration on their costume):
ð: Name of the element
ð Element symbol
ð Atomic number
ð Atomic mass
ð Number of protons
ð Number of electrons (in a neutral atom)
ð Number of neutrons
ð Drawn picture of atom (YOU MUST DRAW IT)
ð Boiling point
ð Melting point
ð State of matter (at room temperature)
ð Uses for element
ð Type of element (metal, nonmetal, metalloid)
ð Group name (halides, lanthanides, noble gases, etc.)
ð Other elements in group
MUST BE COLORFUL AND DETAILED
Project Format (choose ONE):
Poster
Slides
flyer
Pamphlet
Criteria
4-5
3-3.99
2-2.99
0-1.99
Origin
All of the components for the origin criteria are present, explained fully, and are related to the context in an appropriate manner.
One component is missing; or, some components are not clearly explained.
Two components are missing; or, several components are not clearly explained.
More than two components are missing, or all components are not clearly explained.
Background
All of the components for the background criteria are present, explained fully, and are related to the context in an appropriate manner.
One component is missing; or, some components are not clearly explained.
Two components are missing; or, several components are not clearly explained.
More than two components are missing, or all components are not clearly explained.
Powers
All of the components for the criteria of the power are present, explained fully, and are related to the context in an appropriate manner.
One component is missing; or, some components are not clearly explained.
Two components are missing; or, several components are not clearly explained.
More than two components are missing, or all components are not clearly explained.
Other Heroes/Villains
All of the components for the other heroes/villains criteria are present, explained fully, and are related to the context in an appropriate manner.
One component is missing; or, some components are not clearly explained.
Two components are missing; or, several components are not clearly explained.
More than two components are missing, or all components are not clearly explained.
Work Quality
The work is of high quality, clean, neat, and easy to follow.
One component is missing; or, some components are not clearly explained.
Two components are missing; or, several components are not clearly explained.
More than two components are missing, or all components are not clearly explained.
Individual Contribution
The individual participated equally with their partner in the project with little to no drama and minimal prompting.
The individual participated in the project but was slightly less than an equal partner. May have required prompting to participate.
The individual participated, but was less than an equal partner, or required multiple prompts to participate.
Little to no participation in the project, requiring many prompts.
Score:
/30
Answer:
This is something you have to do yourself. The teacher is even letting you have a partner. Nobody is going to do this project for you because it´s your responsibility to finish it on your own.
Explanation:
rutherford called the region that deflected alpha particles
Answer:
Rutherford concluded that these particles were striking... a tiny region of positive charge. Rutherford called the region that deflected alpha particles... a nucleus. The total volume of the nucleus of an atom is... very small compared with the rest of the atom. Except for in the simplist type fo hydrogen atom, all nuclei consist of...
Explanation:
at 20°c, a 0.376 m aqueous solution of ammonium chloride has a density of 1.0045 g/ml. what is the mass % of ammonium chloride in the solution? the formula weight of nh4cl is 53.50 g/ml.
At 20°c, a 0.376 m aqueous solution of ammonium chloride has a density of 1.0045 g/ml. The mass percent of the ammonium chloride in the solution is 2.003%.
The number of moles of a substance can be estimated as:
[tex]\mathbf{number\ of\ moles = \dfrac{mass}{molar \ mass}}[/tex]
Given that:
number of moles = 0.376 Mmolar mass of ammonium chloride = 53.50 g/mlMass = number of moles × molar mass
Mass = 0.376 × 53.50
Mass = 20.116 grams
In one mL of ammonium chloride; the grams of ammonium chloride is:
[tex]\mathbf{= \dfrac{20.116 \ grams}{1000 \ mL}}[/tex]
= 0.020116 g/mL
The mass of ammonium chloride in the solution can be computed as:
[tex]\mathbf{=(\dfrac{mass \ of \ NH_4Cl}{density \ of \ the \ solution})\times 100}[/tex]
[tex]\mathbf{=(\dfrac{0.020116 }{1.0045})\times 100}[/tex]
= 2.003%
Therefore, we can conclude that the mass percent of the ammonium chloride in the solution is 2.003%.
Learn more about ammonium chloride here:
https://brainly.com/question/23387600?referrer=searchResults
Is table salt dissolved in water a homogeneous or heterogeneous mixture
Answer:
heterogeneous
Explanation:
I said so jit
hydrogen is grouped with the alkali metals because it
Answer:
Hydrogen is placed above group in the periodic table because it has ns1 electron configuration like the alkali metals. However, it varies greatly from the alkali metals as it forms cations (H+) more reluctantly than the other alkali metals.
Explanation:
the symbol for the element in period 2 group 13 is
Answer:
Boron
Explanation:
Using the periodic table we can see that Period 2 represents the second row. Group 13 indicates the 13th column.
If yuo put hand sanitizer in a bottle, light a match, drop it in the bottle, what will happen?
Answer: As hand sanitizer dries, it evaporates into gas, which can also catch fire. That’s why the experts recommend that people avoid lighters, matches and fires after using hand sanitizer.
Explanation:
Explanation:
A medida que se seca el desinfectante de manos, se evapora en gas, que también puede incendiarse. Es por eso que los expertos recomiendan que las personas eviten los encendedores, fósforos y fuegos después de usar desinfectante para manos.
What amount of heat (in kJ) is required to convert 19.8 g of an unknown liquid (MM = 83.21 g/mol) at 19.2 °C to a gas at 93.5 °C? (specific heat capacity of liquid = 1.58 J/g･°C; specific heat capacity of gas = 0.932 J/g･°C; ∆Hvap = 22.5 kJ/mol; normal boiling point, Tb = 57.3°C)
The total energy required to convert the unknown liquid to gas at the given temperature is 7.215 kJ.
The given parameters;
mass of the unknown liquid, m = 19.8 gmolar mass of liquid = 83.21 g/molinitial temperature of the liquid, = 19.2 °Cboiling point temperature of the liquid, = 57.3°Cfinal temperature of the liquid = 93.5 °CThe total heat required to convert the liquid to gas is calculated as follows;
H = Heat to raise to boiling temp. + Heat to vaporize the liquid + Heat of gas vapor
The heat required to raise the temperature of the liquid to boiling point;
[tex]H_1 = mc\Delta t\\\\H_1 = 19.8 \times 1.58 \times (57.3 - 19.2)\\\\H_1 = 1,191.92 \ J\\\\H_1 = 1.1919 \ kJ[/tex]
The number of moles of the liquid is calculated as;
[tex]moles= \frac{19.8 \ g}{83.21 \ g/mol} = 0.238 \ mol[/tex]
The heat required to vaporize the liquid;
[tex]H_2 = n H_{vap}\\\\H _2 = 0.238 \times 22.5\\\\H_2 = 5.355\ kJ[/tex]
The heat of the gas vapor is calculated as;
[tex]H_3 = mc_g \Delta t\\\\H_3 = 19.8 \times 0.932 \times (93.5- 57.3)\\\\H_3 = 668.02 \ J\\\\H_3 = 0.668 \ kJ[/tex]
The total energy required to convert the unknown liquid to gas at the given temperature is calculated as;
[tex]H_{total} = 1.1919 \ kJ \ + \ 5.355 \ kJ \ + \ 0.668 \ kJ\\\\H_{total} = 7.215 \ kJ[/tex]
Thus, the total energy required to convert the unknown liquid to gas at the given temperature is 7.215 kJ.
learn more here:https://brainly.com/question/13944094
A school bus travels 270 km in 6 hr. What is its average speed for the trip in km/hr?
Answer:
45km/hr
Explanation:
270/6=45
Draw the circuit symbol that would represent the 9V battery
What are epimers?
How are glucose and manose epimers?
Please Help!
Answer:
Epimers are carbohydrates which vary in one position for the placement of the -OH groupExplanation:
they have a specific type of stereoisomers which have multiple stereo center's but differ from one another, they differ from each other by configuring at the c-2" atom . so, they are epimersCompare and contrast Dalton's atomic theory with modern atomic theory.
Answer:
Postulates of Dalton's Atomic Theory:
1) Atoms can neither be created nor destroyed.
2) During chemical reaction, atoms combine or separate or re-arrange. They combine in simple ratios.
3) All elements are composed of the indivisible particles called atoms.
4) Atoms of a particular element are identical. They have the same mass and volume.
Postulates of modern atomic theory:
1) All matter is composed of atoms.
2) Atoms consist of protons, electrons and neutrons.
3) Atoms of an element may differ in masses. (as in isotopes)
4) The ratio in which elements combine may not be simple.
Similarities:
1) All elements/matter are/is composed of atoms.
2) Atoms can neither be created nor destroyed.
3) During chemical reactions, atom combine or separate or rearrange.
Differences:
1) Dalton's theory said that atoms are indivisible particles but modern theory denies it and calls atom a divisible particle consisting of sub-atomic particles, protons, electrons and neutrons.
2) Dalton's theory said that atoms of the same element have same mass and volume but according to modern theory, it is said that atoms of the same element can differ in mass (as in isotopes).
3) Dalton said that atoms combine in simple ratio but modern theory denies it.
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807I NEED HELP ASAP PLEASE
Answer: I am sorry i couldnt answer but this question is beyond me
Explanation:
A ball exerts a force of 10 newtons on an area of 5 cm2 find the pressure with the formula : pressure = force/area
Answer:
2
Explanation:
10/5
3.7x10^45 molecules of hydrogen gas = how many grams of hydrogen gas
Since we weren't given the moles of hydrogen, we have to find it. However, we can do it all in one step if we set up the equation correctly.
Since Mass = moles × molar mass
& Moles = #molecules ÷ Avogadro's Number
∴ mass = (#molecules ÷ Avogadro's Number) × molar mass
= (3.7 × 10⁴⁵ mcules ÷ (6.022 × 10²³ mcules/mole)) × 1.008 g/mol)
= 6.19 × 10²¹ g
Please help!! Need asap due at 11:59
There are more than 118 naturally occurring elements.Seventy five percent of the universe is Carbon .The earths's crust and human body are made of different elements.But Carbon is an element which is abundant in both.Most objects are made of Carbon with approximately one million Compounds known and over being developed and discovered every year.
the ribosome catalyzes the formation of which bond?
Answer:
the ribosome catalyzes the formation of which bond peptide bonds, peptidyl transfer, the formation of a peptide bond during protein synthesis
Which characteristics of sedimentary rocks allow them to preserve fossils?
O A. high heat, high pressure
O B. high heat, low pressure
O C. low heat, high pressure
O D. low heat, low pressure
which tissue carrys messages to and from the brain
Answer:
nervous tissues
Explanation:
Nervous tissue is found in the brain, spinal cord, and nerves. It is responsible for coordinating and controlling many body activities. ... The cells in nervous tissue that generate and conduct impulses are called neurons or nerve cells. These cells have three principal parts: the dendrites, the cell body, and one axon
credits to the person who provided this info.
answer false or true for each question, (1-5). thanks!
please answer this question correctly
100.0 grams of an isotope with a half-life of 36.0 hours is present at time zero. How much time will have elapsed when 25.00 grams remains?
We have that the time that will have elapsed when 25.00 grams remains is
T=72hours
From the question we are told
100.0 grams of an isotope with a half-life of 36.0 hours is present at time zero. How much time will have elapsed when 25.00 grams remains?
Generally the equation for the Half life is mathematically given as
Where
[tex]X=\frac{25}{100}\\\\X=0.25\\\\Therefore\\\\\frac{1}{2}^n=0.25\\\\n=2 half lives[/tex]
Therefore
T=2*36
T=72 hours
Hence
the time that will have elapsed when 25.00 grams remains is
T=72hours
For more information on this visit
https://brainly.com/question/23366835
what is a acid and how does it react with metals (chemical reaction)?
Explanation:
Acids are substances whose ph is lower than 7.Acids react with most metals to form a salt and hydrogen gas.
Carbon burns with oxygen to produce carbon dioxide gas.
Which of these shows the correct chemical reaction?
O C+0=CO2
O CO, CO2
C +02 + CO2
CO2 = C+0
Answer:
it will help you , but I am not sure it is correct
what is the strongest intermolecular force to be overcome when ethanol is converted from a liquid to a gas?
Answer:
hydrogen bonding
Explanation:
The strongest among them is hydrogen bonding, and the weakest are London dispersion forces.
The strongest intermolecular force to overcome when ethanol is converted from liquid to a gas is hydrogen bonding.
Intermolecular forces are forces that are a weaker force of attraction than intramolecular forces.
Intermolecular forces are forces between molecules and hold these molecules together.
Hydrogen bonding is an example of intermolecular forces between the OH group in the alcohol.
During the conversion of ethanol from liquid to gas state, hydrogen bonding occurs between the partial negative charge in the oxygen and the partial positive charge in the hydrogen.
Learn more about intermolecular force here:
https://brainly.com/question/13588164
A cup of coffee cools to 15 °C from 30 ° C. What is the change in temperature?
Answer:
15° C
Explanation:
30-15=15
checking* 15+15=30 or 15x2=30
The arrangement of particles is most ordered in a sample of
1.
NaCl(aq)
2.
NaCl(l)
3.
NaCl(g)
4.
NaCl(s)
PLEASE HELP
We have that the arrangement of particles of NaCl is most ordered in a sample of
NaCl(s)
i.e solid NaCl
From the question we are told
The arrangement of particles is most ordered in a sample of
1. NaCl(aq)
2. NaCl(l)
3. NaCl(g)
4. NaCl(s)
NaCl Generally known as sodium chloride or salt exist in four main states as shown
1. NaCl(aq)
2. NaCl(l)
3. NaCl(g)
4. NaCl(s)
Mow in a subject of its arrangement of particles we can see that as its state changes from gaseous through to solid it gains in form and arrangement of particles
Therefore
The arrangement of particles of NaCl is most ordered in a sample of
NaCl(s)
i.e solid NaCl
For more information on this visit
https://brainly.com/question/1641336
Which of the following physical properties would tell you about an element's mass per unit volume ratio?
hardness
boiling point
crystalline shape
density
all of the above
Answer:
It's the density
What is the difference between a molecule and compound?
A compound is a special type of molecule where the atoms that form the molecule are of different elements.