A scientist who collects and analyzes DNA from a crime scene is a
Answer:
forensic scientist
Explanation:
forensic science is the discipline in which professionals use scientific means to analyze physical crime evidence. this evidence is then presented in court in order to help determine the innocence or guilt of a specific suspect.
Answer:
Its a forensic scientist :D
Explanation:
I took a test and got it wrong but it showed the right answer and its a forensic scientist
(don't ask how i got it wrong i was rushing!!)
What volume. In liters, of H2O(g) measured at STP is produced by the combustion of 15.63 g of natural gas (CH4) according to the following equation? CHale) +20269) CO2 + 2H2008)
Answer:
V = 43.95 L
Explanation:
Given data:
Mass of CH₄ decomposed = 15.63 g
Volume of H₂O produced at STP = ?
Solution:
Chemical equation:
CH₄ + 2O₂ → 2H₂O + CO₂
Number of moles of CH₄:
Number of moles = mass/molar mass
Number of moles = 15.63 g/ 16 g/mol
Number of moles = 0.98 mol
Now we will compare the moles of H₂O with CH₄.
CH₄ : H₂O
1 : 2
0.98 : 2×0.98 = 1.96 mol
Volume of hydrogen:
PV = nRT
1 atm × V = 1.96 mol × 0.0821 atm.L/mol.K × 273.15 K
V = 43.95atm.L / 1atm
V = 43.95 L
The atomic masses of 20Ne (90.48 percent), 21Ne (0.27 percent), and 22Ne (9.25 percent) are 19.9924356, 20.9938428, and 21.9913831 amu, respectively. Calculate the average atomic mass of neon. The percentages in parentheses denote the relative abundance
Answer:
20.180042 amu
Explanation:
From the question given above, the following data were obtained:
Isotope A (20Ne)
Mass of A = 19.9924356 amu
Abundance (A%) = 90.48%
Isotope B (21Ne):
Mass of B = 20.9938428 amu
Abundance (B%) = 0.27%
Isotope C (22Ne):
Mass of C = 21.9913831 amu
Abundance (C%) = 9.25%
Average atomic mass of Neon =.?
The average atomic mass of Neon can be obtained as follow:
Average atomic mass = [(mass of A × A%)/100] + [(mass of B × B%)/100] + [(mass of C × C%)/100]
= [(19.9924356 × 90.48)/100] + [(20.9938428 × 0.27) /100] + [(21.9913831 × 9.25) /100]
= 18.0891557 + 0.05668338 + 2.03420294
= 20.180042 amu
Therefore, the average atomic mass of Neon is 20.180042 amu
Calculate the number of atoms present in .20 moles of H20.
Answer:
20 moles = (96.7+)
345%20 moles inter = h20
h2+345%20 moles
kalkadanc = jani+CARSORI
564 MOLES
Explanation
we have to plus the moles that we can get the answer and u should now the formula of kalkadanc and just % will get to the correct answer.
i think u may understand and this is the correct answer i had practice this too much
1 point
Which element requires the least amount of energy to remove its valence electron(s)?
barium
chlorine
oxygen
carbon
How many grams of Fe can be produced when 6.50 g of Fe2O3 reacts?
Answer:
Mass of Fe produced = 4.468 g
Explanation:
Given data:
Mass of Fe produced = ?
Mass of Fe₂O₃ react = 6.50 g
Solution:
Chemical equation:
2Fe₂O₃ → 4Fe + 3O₂
Number of moles of Fe₂O₃ ;
Number of moles = mass/molar mass
Number of moles = 6.50 g/159.69 g/mol
Number of moles = 0.04 mol
Now we will compare the moles of iron and ironoxide.
Fe₂O₃ : Fe
2 : 4
0.04 : 4/2×0.04 = 0.08 mol
Mass of iron produced:
Mass = number of moles × molar mass
Mass = 0.08 mol × 55.85 g/mol
Mass = 4.468 g
please helppp
which one??????????
formal charge of hcooh
Answer:
What is the question?
Please help I will give brainiest
Answer:
1. Least
2. Most
Answer:
1st one is less 2nd is greater
Explanation:
25. Which of the following statements concerning atomic structure is/are correct?
1. The nucleus contains most of an atom's mass.
2. The nucleus contains all the positive charge of an atom.
3. Electrons surround the nucleus and account for the majority of an atom's volume.
1 only
2 only
3 only
2 and 3
1, 2, and 3
Answer:
It would be 2 and 3
The image shows the structure of an atom, I hope it helps :)
To see the number of atoms of an element in a given molecule we need to multiply stoichiometry to the number that is written on the foot of the element that is stoichiometry. Therefore, the correct option is option 2,3.
What is atom?Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.
In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. So overall the charge of nucleus is due to only proton, not by neutron. The nucleus contains all the positive charge of an atom. Electrons surround the nucleus and account for the majority of an atom's volume.
Therefore, the correct option is option 2,3.
To know more about atom, here:
https://brainly.com/question/13518322
#SPJ2
A neutral atom becomes a positive ion when it
Answer:
Neutral atoms can be turned into positively charged ions by removing one or more electrons.
Explanation:
If there is an atom that has 9 protons and 9 electrons, removing an electron from the atom will gain a postive charge.
A beverage manufacturer wants to increase The solunility of carbon dioxide in its carbonated drinks as beverages produced which action will increase the solubility of CO2 gas the most
A. Decreasing the pressure on it
B. Increasing stirring
C. Decreasing its temperature
D. Increasing its temperature
Answer: C
Explanation:
When a material gains thermal energy and melts, it is undergoing a physical change.
Answer:
True, it undergoes a physical change.
Explanation:
A physical change is a change that does not change the chemical makeup of a material. This includes altering its shape.
What evidence should Mitchell collect to BEST support the second law of thermodynamics?
Answer:
The Second Law of Thermodynamics poses an insurmountable problem for ... More time will make things worse for the Darwinist, not better. ... error fail-safe and proof-reading devices utilized for quality control, assembly ... No one really supports the idea that the sun + non life = life
Explanation:
According to the second law of thermodynamics, the energy of the universe is conserved but the entropy of the universe is continuously increasing.
What is the second law of thermodynamics?The second law of thermodynamics put some restrictions on the direction of heat transfer and attainable efficiencies of heat engines. This law stated that any spontaneously happening process will lead to an escalation in the entropy (S) of the universe.
This law explains that the entropy of an isolated system will never decrease with time. Mathematically, the 2nd law of thermodynamics:
ΔS (universe) > 0
where ΔS of the universe is the change in the entropy of the universe.
The second law of thermodynamics provides the criterion for the feasibility of any physical or chemical process. A physical or chemical process cannot take place unless it must follow both the 1st and 2nd laws of thermodynamics.
Learn more about second law of thermodynamics, here:
https://brainly.com/question/1604031
#SPJ2
Ram has power of 550 watt.What does it mean?
Answer:
for electricity, watts as in back to the future "1.21 jigga watts"!
Explanation:
Answer the question below
Answer:
C
Explanation: I think
Predict and write the charges and symbols of the monatomic ions formed by the following atoms: bromine rubidium
Answer: The monoatomic ions formed by bromine and rubidium are [tex]Br^-[/tex] and [tex]Rb^+[/tex] respectively.
Explanation:
When an atom accepts an electron negative charge is created on atom and is called as anion. When atom loses an electron positive charge is created on atom and is called as cation.
The atomic number of bromine and rubidium is 35 and 37 respectively. So, the number of electrons is equal to 35 and 37 respectively. Bromine will gain one electron and rubidium will lose one electron to attain stable electronic configuration to form [tex]Br^-[/tex] and [tex]Rb^+[/tex] respectively.
[tex]Br:35:1s^22s^22p^63s^23p^64s^23d^{10}4p^5[/tex]
[tex]Br^-:36:1s^22s^22p^63s^23p^64s^23d^{10}4p^6[/tex]
[tex]Rb:37:1s^22s^22p^63s^23p^64s^23d^{10}4p^63s^1[/tex]
[tex]Rb^+:36:1s^22s^22p^63s^23p^64s^23d^{10}4p^6[/tex]
Solid nickel reacts with aqueous lead (II) nitrate to form solid lead. What is the net ionic equation for this reaction? • Hint: In this reaction, nickel exhibits its most common oxidation state of +2. • Be sure to include the charge for each ion in the net ionic equation. Provide your answer below: (s) + (aq) → *(n)
Answer:
Pb²⁺(aq) --> Ni²⁺(aq)
Explanation:
The equation of the reaction is given as;
Ni(s) + Pb(NO₃)₂(aq) --> Pb(s) + Ni(NO₃)₂(aq)
In writing the ionic equation, we break the aqueous compound into ions. The solid and liquid compounds are ignored.
We have;
Pb²⁺(aq) + NO₃²⁻(aq) --> Ni²⁺(aq) + NO₃²⁻(aq)
Canceling the spectator ions;
Pb²⁺(aq) --> Ni²⁺(aq)
Answer:
Ni(s)+Pb2+(aq)→Ni2+(aq)+Pb(s)
Explanation:
The complete ionic equation of this reaction is
Ni(s)+Pb2+(aq)+2 NO−3(aq)→Ni2+(aq)+2 NO−3(aq)+Pb(s)
The nitrate ions are spectator ions and can be removed from the equation, giving us
Ni(s)+Pb2+(aq)→Ni2+(aq)+Pb(s)
Describe how simple distillation is used to separate water from an aqueous solution of sodium
sulfate.
Answer:
hbyiy
Explanation:
Why do gases diffuse more quickly than liquids?
Choose the correct answer.
A) Liquids can be compressed easily.
B)The particles in gases are not mobile.
C)Liquids are always at lower temperatures than gases.
D)Gas particles move rapidly and have space between them.
Answer:
D)Gas particles move rapidly and have space between them.
Explanation:
Matter exists in three states namely: solids, liquids and gases. The particles contained in these three states are different from one another. In the gaseous state, the particles are FAR APART from one another i.e. space exists and they move at a very fast rate in contrast to the particles of a liquid, which have less space and move slower.
This rapid movement of gas particles within a less restricted space accounts for the reason why gaseous substances DIFFUSE more quickly than liquids.
what elements make up duralumin( an alloy)?
Answer:
In addition to aluminium, the main materials in duralumin are copper, manganese and magnesium.
Answer:
The original composition has been varied for particular applications; it may contain about 4 percent copper, 0.5–1 percent manganese, 0.5–1.5 percent magnesium, and, in some formulations, some silicon.
in the following chemical reaction between H_2 and Cl_2 to produce HCl, what is the sum of the mass of HCl produced plus the mass of left over reactants when 0.40 g of H_2 completely reacts with 12.35 g of Cl_2?
H_2(g) + Cl_2(g) → 2HCl(g)
Answer:
Left over mass of hydrogen = 0.06 g
Mass of HCl produced = 12.41 g
Explanation:
Given data:
Mass of H₂ = 0.40 g
Mass of Cl₂ = 12.35 g
Mass of left over reactant = ?
Mass of HCl produced = ?
Solution:
Chemical equation:
H₂ + Cl₂ → 2HCl
Number of moles of H₂:
Number of moles = mass / molar mass
Number of moles = 0.40 g/ 2 g/mol
Number of moles = 0.2 mol
Number of moles of Cl₂:
Number of moles = mass / molar mass
Number of moles = 12.35 g/ 71 g/mol
Number of moles = 0.17 mol
Now we will compare the moles of HCl with H₂ and Cl₂.
H₂ : HCl
1 : 2
0.2 : 2×0.2 = 0.4
Cl₂ : HCl
1 : 2
0.17 : 2 × 0.17 = 0.34
Chlorine is limiting reactant.
Mass of HCl produced:
Mass = number of moles × molar mass
Mass = 0.34 mol × 36.5 g/mol
Mass = 12.41 g
Leftover mass of hydrogen:
Cl₂ : H₂
1 : 1
0.17 : 0.17
Number of moles of H₂ react with Cl₂ are 0.17.
Moles remain unreacted = 0.2 - 0.17 = 0.03 mol
Mass left over:
Mass = number of moles × molar mass
Mass = 0.03 mol × 2 g/mol
Mass = 0.06 g
The sum of the mass of HCl produced plus the mass of left over reactants is:
Mass of hydrogen = 0.06 g
Mass of HCl = 12.41 g
Chemical ReactionGiven:
Mass of H₂ = 0.40 g
Mass of Cl₂ = 12.35 g
Mass of left over reactant = ?
Mass of HCl produced = ?
Chemical equation: H₂ + Cl₂ → 2HClNumber of moles of H₂:
Number of moles = mass / molar mass
Number of moles = 0.40 g/ 2 g/mol
Number of moles = 0.2 mol
Number of moles of Cl₂:
Number of moles = mass / molar mass
Number of moles = 12.35 g/ 71 g/mol
Number of moles = 0.17 mol
The moles of HCl with H₂ and Cl₂.
H₂ : HCl
1 : 2
0.2 : 2×0.2 = 0.4
Cl₂ : HCl
1 : 2
0.17 : 2 × 0.17 = 0.34
The chlorine is limiting reactant.
Mass of HCl produced:
Mass = number of moles × molar mass
Mass = 0.34 mol × 36.5 g/mol
Mass = 12.41 g
Leftover mass of hydrogen:
Cl₂ : H₂
1 : 1
0.17 : 0.17
Number of moles of H₂ react with Cl₂ are 0.17.
Moles remain unreacted = 0.2 - 0.17 = 0.03 mol
Mass left over:
Mass = number of moles × molar massMass = 0.03 mol × 2 g/molMass = 0.06 gLearn more about "Moles":
https://brainly.com/question/7287712?referrer=searchResults
PLEASE HELP IM TIMED
Which of the following is not an oxidation-reduction reaction?
Upper X e upper F subscript 6 (s) right arrow upper X e upper F subscript 4 (s) plus upper F subscript 2 (g).
2 upper C s (s) plus upper I subscript 2 (g) right arrow 2 upper C s upper I (s).
2 upper H subscript 2 upper S upper O subscript 4 (a q) plus 2 upper B a (upper O upper H) subscript 2 (a q) right arrow 2 upper B a upper S upper O subscript 4 upper H subscript 2 upper O (l).
Upper Z n (s) lus 2 upper A g upper N upper O subscript 3 (a q) right arrow upper Z n (upper N upper O subscript 3) subscript 2 (a q) plus upper A g (s).
Answer: choice 2
Explanation:
What is the relationship between temperature and pressure
On average what is the time between collisions of a xenon atom at 300 K and (a) one torr pressure; (b) one bar pressure.
Answer:
(a). 132 × 10^-9 s = 132 nanoseconds.
(b)..176.5 pico-seconds.
Explanation:
(a). At one torr, the first thing to do is to find the speed and that can be done by using the formula below;
Speed = [ (8 × R × T)/ Mm × π]^1/2.
Where Mm = molar mass, T = temperature and R = gas constant.
Speed= [ ( 8 × 8.314 × 300)/ 131.293 × π × 10^-3)^1/2. = 220m/s.
The next thing to do now is to calculate for the degree of collision which can be calculated by using the formula below;
Degree of collision = √2 × π × speed × d^2 × pressure/ K × T.
Note that pressure = 1 torr = 133.32 N/m^2 and d = collision diameter.
Degree of collision = √2 × π × 220 × (4.9 × 10^-10)^2 × 133.32/ 1.38 × 10^-23 × 300.
Degree of collision = 7.55 × 10^6 s^-1.
Thus, 1/ 7.55 × 10^6. = 132 × 10^-9 s = 132 nanoseconds.
(b). At one bar;
1/10^5 × 10^3 × 56.65 = 1.765 × 10^-10 = 176.5 pico-seconds.
The diagram shows currents that form as water is heated. Which would most likely contain this same type of current? the air above a wildfire a carton of milk in a refrigerator a snowdrift on a shady mountainside a boulder in a hot desert
Answer:
the answer is A
Explanation:
edg 2020
Answer:
the air above a wildfire/A
Explanation:
Hello I was wondering if anyone knew how to draw the molecular geometry of fentanyl. I already did the Lewis structure.
Answer:
i dont
Explanation:
A gas has a density of 1.57 g/L at 40.0 °C and 2.00 atm of pressure. What is the identity of the gas?
Answer:
Neon
Explanation:
Step 1: Given and required data
Density of the gas (ρ): 1.57 g/LTemperature (T): 40.0°CPressure (P): 2.00 atmIdeal gas constant (R): 0.08206 atm.L/mol.KStep 2: Convert T to Kelvin
We will use the following expression.
K = °C + 273.15 = 40.0 + 273.15 = 313.2 K
Step 3: Calculate the molar mass of the gas (M)
For an ideal gas, we will use the following expression.
ρ = P × M/R × T
M = ρ × R × T/P
M = 1.57 g/L × 0.08206 atm.L/mol.K × 313.2 K/2.00 atm
M = 20.17 g/mol
The gas with a molar mass of 20.17 g/mol is Neon.
In Chemistry, the gas with a molar mass of 20.18 g/mol is neon (Ne) and this is the identity of the gas.
Given the following data:
Density of gas = 1.57 g/LTemperature = 40.0°CPressure = 2.00 atmScientific data:
Ideal gas constant, R = 0.0821 L⋅atm/mol⋅KConversion:
Temperature = 40.0°C to K = [tex]273 +40=313\;K[/tex]
To determine the identity of this gas, we would apply the ideal gas law equation;
[tex]MM = \frac{R\rho T}{P}[/tex]
Where;
P is the pressure.MM is the molar mass of a gas.R is the ideal gas constant.T is the temperature.[tex]\rho[/tex] is the density of a gas.Substituting the given parameters into the formula, we have;
[tex]MM=\frac{0.0821 \times 1.57 \times 313}{2} \\\\MM=\frac{40.35}{2}[/tex]
Molar mass = 20.18 g/mol.
In Chemistry, the gas with a molar mass of 20.18 g/mol is neon (Ne).
Read more: https://brainly.com/question/20317432
4. Question: What effect does the amount of light have on plant growth?
What is the specific rotation of a sample of carvone that is an equal mixture of the R and S enantiomers
Answer:
Zero
Explanation:
An an equal mixture of the R and S enantiomers of carvone is called a racemic mixture.
In a racemic mixture, the R enantiomer rotates plane polarized light in one direction while the S enantiomer rotates plane polarized light in another direction.
This cancels out the rotation due to each enantiomer since they are equal in magnitude but opposite in direction leading to a specific rotation of zero for the racemic mixture.