True, sometimes it is hard to find evidence at the scene of a suspicious fire because the act of putting out a fire is destructive.
Firefighters must handle the area as a medical emergency incident in addition to a fire scene. The victim should be treated as evidence and kept in tact.Why is it difficult to find evidence of arson?
All unintentional causes of a fire-related incident must be eliminated before it can be deemed arson; this requires strong evidence that the fire was started intentionally. Arson is challenging to establish and later prosecute for this reason.Why is fire investigation difficult?
For three key reasons, arson investigations are challenging: The arsonist can prepare the fire in advance and bring all the necessary equipment with them. There is no requirement that the arsonist be present while the act is committed. Evidence linking the arsonist to the crime is destroyed by the fire itself.Learn more about fire investigation
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Write the formula and determine the percent by mass of the salt in barium hydroxide octahydrate *
(show work)
Answer:
315.51g/mol
Explanation:
137(33 + (16.00 + 1.01) 2 + 8 [1.01 (2) + 16.00] = 315.51g/mol
For the rxn CaCo3(s)+2Hcl(aq)_CaCl(aq)+Ca2(g)+H2O(l)68.1 g solid CaCo3 is mixed with 51.6Hcl what number of grams of Co2 will be produced
Answer:
29.9 g of CO₂ will be produced by the reaction.
Explanation:
This is the reaction:
CaCO₃(s) + 2HCl (aq) → CaCl₂(aq) + CO₂(g) + H₂O(l)
First of all, we state the moles of each reactant:
68.1 g . 1mol/ 100.08g = 0.680 mol of carbonate
51.6 g . 1 mol/36.45g = 1.46 mol of acid.
The solid salt is the limiting reactant. Ratio is 2:1
2 moles of acid can react to 1 mol of salt
1.46 mol of acid may react with (1.46 . 1)/2 = 0.727 moles
As we only have 0.680 moles of salt, we do not have enough.
Let's work at the product side. Ratio is 1:1
1 mo of salt can produce 1 mol of gas
0.680 moles will produce 0.680 moles of gas
We convert the moles to mass → 0.680 mol . 44g / 1mol = 29.9 g of CO₂
The number of grams of Co2 should be produced is 29.9 g.
Calculation of the number of grams:Since
CaCO₃(s) + 2HCl (aq) → CaCl₂(aq) + CO₂(g) + H₂O(l)
So,
68.1 g . 1mol/ 100.08g = 0.680 mol of carbonate
51.6 g . 1 mol/36.45g = 1.46 mol of acid.
Now the ratio should be 2:1 for the solid salt
And, there is 2 moles of acid can react to 1 mol of salt
So,
1.46 mol of acid may react with (1.46 . 1)/2 = 0.727 moles
Now the product side the ratio is 1:1
So, that means
1 mo of salt can produce 1 mol of gas
So, the no of grams should be
= 0.680 mol . 44g / 1mol
= 29.9 g of CO₂
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Na on the periodic table is the symbol for what?
Answer:
sodium
Explanation:
Na is the symbol for sodium on the periodic table
Answer: Sodium is a chemical element with the symbol Na (from Latin "natrium") and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is 23 Na.
Explanation:
What conclusion can be drawn from the fact that water can decompose into oxygen and hydrogen?
Answer:
hydrogen is collected at negative chose and oxygen is collected at positive anode. Hydrogen is double in volume than oxygen. 2H2O = 2H2 + O2.
Explanation:
and GAMER PHROG
how many molecules are there in 1.5 mol of methane
Answer: A mole of something means that there are 6.02 X 10^23 of that something. So, a mole of methane molecules is 6.02 X 10^23 methane molecules. So, 1.5 moles of methane will contain 1.5*(6.02 X 10^23) = 9.0 X 10^23 methane molecules
Explanation:
Which changes would cause an increase in the resistance of a wire? Check all that apply.
increasing its temperature
decreasing its temperature
using a longer wire
using a shorter wire
m using a thicker wire
using a thinner wire
Answer:
Increasing its temperature.
Longer
and thinner
Explanation:
e2021
The resistance of a wire increases by increasing its temperature, using a longer wire and using a thinner wire.
Resistivity of a wireThe resistivity of wire describes the opposition to the flow of current in the wire.
[tex]R = \frac{\rho L}{A} \\\\\rho = \frac{RA}{L} \ (ohm-meter)[/tex]
where;
R is the resistance (ohms)ρ is resistivity of the wire (ohm-meter)L is length of the wire (m)A is area of the wire (m²)From the formula above, the resistance of a wire increases with
increase in the length of the wiredecrease in thickness (radius) of the wireincrease in temperatureLearn more about resistance of a wire here: https://brainly.com/question/469388
No attempt was made to test sodium with hydrochloric
acid. Why not?
Answer:
the reaction is violent and quick
Explanation:
explain why dilute trioxosulphate vi acid is not used to prepare carbon 4 oxide from calcium
trioxocarbonate 4
Answer:
H2SO4 cannot be used with CaCO3 to produce CO2 gas
Explanation:
Because it does not dissolve in water- it forms a barrier on the surface of the unreacted CaCO3 which prevents any further reaction. A small volume CO2 is produced, this stops in short time.
I hope this helps :)
The desert climate or arid climate, is a climate which there is an excess of evaporation over precipitation. During the days, the temperatures are very high and dry. During nightfall, temperatures drop dramatically and it gets very cold. In three to four sentences, describe one plant and one animal that you would expect to find in the arid biome. Support your answer with the abiotic factors in the biome. *
These desert dwelling, nocturnal creatures are very tough and low maintenance. Scorpions' exoskeletons and venomous stingers give them great protection, and their low food and water needs and ability to slow down their metabolism allow them to survive in the harshest environments.
calculate 28.1g of silicon to moles
Answer:
2.53•10^23 atoms
Explanation:
23 is the exponent btw
SCIENCE
Does combustion need oxygen?
A. Yes
B. No
Answer: a. Yes
Explanation:
Answer:
A. yes
Explanation:
In order to burn this fuel, oxygen is needed, as it is with any fire. The waste products from the combustion process are water and carbon dioxide. Thus, we breathe because oxygen is needed to burn the fuel (sugars and fatty acids) in our cells to produce energy The air we breathe contains about 21% oxygen.
The yellow light given off by a sodium vapor lamp has a wavelength of 589nm. What is the frequency of this radiation? Please show all work.
Answer:
5.09 x 10⁶ s⁻¹ = 5.09 x 10⁶ Hz
Explanation:
The relation between frequency (ν) and wavelength (λ) is given by:
λ = c/ν
where c is the speed of light (2.998 m/s) and it is a constant.
So, we first convert the wavelength from nanometers (nm) to meters (m) (1 nm = 1 x 10⁻⁹):
λ= 589 nm x (10⁻⁹ nm/1 m) = 5.89 x 10⁻⁷ m
Then, we calculate the frequency from the equation:
λ = c/ν ⇒ ν = c/λ = (2.998 m/s)/(5.89 x 10⁻⁷ m) = 5.09 x 10⁶s⁻¹ = 5.09 x 10⁶ Hz
(iii) Observe the following diagram and answer the following questions :
X Х
Y
(A) Identify elements X and Y.
(B) Do these elements belong to the same group?
(C) Which element is more electropositive in nature? Why?
Name the element which has twice the number of electrons in its second shell as in the first shell write it's electronic configuration also.
name three layers of our skin
changing the number of _______ makes an atom stable or unstable and creates different isotopes of the same element with a different ______ (pick two that best fits.)
a.) atomic mass
b.) atomic number
c.) protons
d.)neutrons
e.)electrons
f.) ion
g.)neutral
The neutrons are the neutral sub-atomic particles present in the nucleus. The variation in the number of neutrons produces isotopes that have different atomic mass. Thus, options 1. d and 2. a are correct.
What is an isotope?An isotope is said to be an atom of an element that have a different atomic mass but the same atomic number due to the variation in the neutrons in the nucleus. The neutrons have a neutral charge that makes the atom stable.
When a neutron is added or lost it makes the nucleus of the atom unstable leading to radioactive decay. The isotopes have the same constant number of protons in their nucleus.
The atomic number of the atom remains the same due to the stable proton number but varies the atomic mass due to the change in the number of neutrons.
Therefore, options d and a. neutrons and atomic mass are the correct blanks.
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Karla is reading about a type of single-celled microorganism that can live inside the human body. This type of organism can either be harmful or harmless to people, depending on the type. One harmless type lives in the intestines and helps the body digest food. One harmful type can cause strep throat. Which type of organism is Karla most likely reading about?
A bacteria
B fungi
C parasites
D viruses
please help
Answer:
its bacteria
Explanation:
Single-celled organisms can directly take in nutrients from their outside ... Figure 1. The digestive systems of representative animals. Images from ... There are two types of animal body plans as well as two locations fordigestion to occur
Answer:
A bacteria
Explanation:
i did it LOL
Drag each label to the correct location.
We use specific words to describe each type of change in state. Label the arrows to describe the changes of state they
represent
gas
liquid
solid
melting freezing condensation
evaporation sublimation
deposition
Which type of model is described below? A scientist thinks of the inside of a tree as being like a giant straw that can suck up water A. Atomic model B. Physical model C. Mathematical model D. Conceptual model
Answer:
B. Physical model
Explanation:
Out of the four of them this is the one that makes the most sense
Think about a synthetic material that you use every day. How
could that material be improved to better fit its function?
explanation: Synthetic fiber or synthetic fibre (in British English; see spelling differences) are fibers made by humans through chemical synthesis, as opposed to natural fibers that are directly derived from living organisms. They are the result of extensive research by scientists to improve upon naturally occurring animal and plant fibers. In general, synthetic fibers are created by extruding fiber-forming materials through spinnerets, forming a fiber. These are called synthetic or artificial fibers. Synthetic fibers are created by a process known as polymerization, which involves combining monomers to make a long chain or polymer. The word polymer comes from a Greek prefix "poly" which means "many" and suffix "mer" which means "single units". (Note: each single unit of a polymer is called a monomer). There are two types of polymerization: linear polymerization and cross-linked polymerization.
Complete the sentence. Atoms form chemical bonds to satisfy the rule and to become Å Done Intro -
Answer:
Sorry
Explanation:
I m very sorry I don't know this
Which federal agency makes sure federal wildlife laws are followed?
US Forest Service
US Fish and Wildlife Service
Bureau of Land Management
National Park Service
Answer:
us fish and wildlife service
Explanation:
the 2nd choice
Answer:
US Fish and Wildlife Service
1. Which word has the same phoneme as grew, rude, and truth?
A. thumb
B. sure
C. look
D. scoot
Answer:
B-Sorry if this isn't right :/ Good luck.
Explanation:
Answer:
D. Scoot
Explanation:
Grew, Rude and truth all have the sound /OO/ scoot follows that pattern.
difference between solute and solvent
When one substance dissolves into another, a solution is formed. A solution is a homogeneous mixture consisting of a solute dissolved into a solvent . The solute is the substance that is being dissolved, while the solvent is the dissolving medium. Solutions can be formed with many different types and forms of solutes and solvents.
Explanation:
solute are substance that dissolve in solvent
solvent are substance that dissolve solute
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The relative humidity is 100%, and the temperature is hot. In a few sentences, explain how the weather would change if the temperature drops and becomes cool.
Answer:
Humdity would decrease hence temprature would do the same, hence tundra are called deserts at times.
Explanation:
If you keep on decreasing the temperature without changing the air's moisture content significantly, eventually you'll reach 100 percent relative humidity, and then water vapor will start to condense to form dew.
What happens when humidity is at 100% and the temperature drops?Dew Point. When the relative humidity reaches 100 percent, dew forms. Dew point refers to the temperature at which air reaches saturation by water molecules. Warmer air can hold more water molecules, and as that warm air cools, it loses water vapor in the form of condensation.
What happens when it reaches 100% relative humidity?When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid-vapor. Thus, the saturation level of air is related to the air's temperature.
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Al +CI = Al CI3
how do i solve this
Thermal expansion occurs when particles of matter move farther apart as temperature increase. True or false ?
Answer:
true
Explanation:
Describe the arrangement and motion of the particles in liquid stearic acid.
Answer:
Its density is exactly the same as that of pure stearic acid. Its boiling point is the same as that of pure stearic acid. Its melting point is different from pure stearic acid.
please help me out i will give you brainlist. 0.500 is wrong
============================================
Work Shown:
Using the periodic table, we see that
1 mole of carbon = 12 grams1 mole of oxygen = 16 gramsThese are approximations and these values are often found underneath the atomic symbol. For example, the atomic weight listed under carbon is roughly 12.011 grams. I'm rounding to 2 sig figs in those numbers listed above.
So 1 mole of CO2 is approximately 12+2*16 = 44 grams. The 2 is there since we have 2 oxygens attached to the carbon atom.
-------------------
Since 1 mole of CO2 is 44 grams, we can use that to convert from grams to moles.
11.0 grams of CO2 = (11.0 grams)*(1 mol/44 g) = (11.0/44) mol = 0.250 mol of CO2
In short,
11.0 grams of CO2 = 0.250 mol of CO2
This is approximate.
We don't need to use any of the information in the table.
Answer:
.250
Explanation:
What is the symbol for Sodium?
Na
S