Answer:
a risk to human health or the environment arising from biological work, especially with microorganisms.
Explanation:
Is atomic radius a periodic property of atoms??
Name the region of the atom where protons and
neutrons are located. This region is indicated by
label B.
Name the region of the atom where electrons are
located. This region is indicated by label A.
DONE
Answer:
B. Nucleus
A. Orbitals
Explanation:
Ed22
The region of the atom where protons and neutrons are located (B) is called the nucleus.
The region of the atom where electrons are located (A) is called orbits.
In an atom, the nucleus is the central core that contains protons and neutrons. It is a tiny, dense region located at the center of the atom. Protons have a positive charge, while neutrons are electrically neutral (have no charge). The number of protons in the nucleus determines the element's identity.
Orbits (also called electron shells or energy levels) are the regions around the nucleus where electrons are found. Electrons are negatively charged particles that move within these orbits. Each orbit has a specific energy level, and electrons closer to the nucleus have lower energy levels. Electrons occupy the lowest available energy levels first before moving to higher levels as the atom gains more electrons.
Learn more about Atoms, here:
https://brainly.com/question/1566330
#SPJ5
The complete question is shown in the image attached below -
How are carbon dioxide (CO2) levels in the atmosphere affected by tectonic uplift of rocks and their resultant chemical weathering?
Answer:
The levels of carbon dioxide (CO2) in the atmosphere are reduced
Explanation:
Tectonic uplift refers to the process by which the surface of the earth slowly rises either due to increasing upward force applied from the plates below the surface or decreasing downward force or weight of objects like melting glaciers acting from above. During uplift, land, as well as the sea floor rises forming mountains, plateaus and volcanic Islands.
During the process of weathering, carbon dioxide present in air combines with rainwater and forms carbonic acid. This acidic rainwater then falls on uplifted mountains and rocks weathering them in the process. Minerals present in the rock such as calcium, magnesium and sodium then combine with bicarbonate ions to form carbonates such as calcium carbonate, magnesium carbonate which are found in shells of living and dead organisms and also form rocks such as limestone. In this way, carbon dioxide is removed from the atmosphere.
How many molecules are in 6.00 mol He?
HELP!!!!!
The enthalpy of combustion of naphthalene (MW = 128.17 g/mol) is -5139.6 kJ/mol. How much energy is produced by burning 0.8210 g of naphthalene?
The energy produced : -32.89 kJ
Further explanationDelta H reaction (ΔH) is the amount of heat / heat change between the system and its environment
(ΔH) can be positive (endothermic = requires heat) or negative (exothermic = releasing heat)
The enthalpy of combustion of naphthalene (MW = 128.17 g/mol) is -5139.6 kJ/mol.
For 0.8210 g of naphthalene :
mol =
[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{0.8210}{128.17}=0.0064[/tex]
The energy produced :
[tex]\tt Q=\Delta H\times n(mol)\\\\Q=-5139.6\times 0.0064=-32.89~kJ[/tex]
Which of the following substances has bonds with the greatest ionic character?
A) CCl4
B) CuCl2
C)CaCl2
D)NCl3
Answer:
Explanation:
because Ca is of second group they have low ionization energy when react with chlorine they have more ionic character than other in given options
Consider the reaction of glucose with oxygen: C6H12O6(s) + 6O2(g) Right arrow. 6CO2(g) + 6H2O(l)
The enthalpy of formation (Delta.Hf) for C6H12O6(s) is –1,273.02 kJ/mol, Delta.Hf for CO2(g) is –393.5 kJ/mol, and
Delta.Hf for H2O(l) is –285.83 kJ/mol. What is Delta.Hf for O2(g)?
Which equation should be used to calculate Delta.Hrxn for this reaction?
(-393.5kJ/mol + (-285.83 kJ/mol))-(-1,273.02 kJ/mol)
-1,273.02 kJ/mol - ((6 mol)(-393.5 kJ/mol) + (6 mol)(-285.83 kJ/mol))
((6 mol)(-393.5 kJ/mol) + (6 mol)(-285.83 kJ/mol)) - (1 mol)(-1,273.02 kJ/mol)
What is Delta.Hrxn for this reaction?
answer: first, third, -2803
We can effectively that the correct equation of the reaction is correctly written as ((6 mol)(-393.5 kJ/mol) + (6 mol)(-285.83 kJ/mol)) - (1 mol)(-1,273.02 kJ/mol).
What is the heat of reaction?The heat of reaction is the heat that could be absorbed or evolved in a reaction. We know that a reaction could be an exothermic or an endothermic reaction. In an exothermic reaction, energy is given out while an endothermic reaction is one in which heat is absorbed.
Having said this, we know that the reaction is a combustion reaction. Heat is always given out in a combustion reaction thus we know that the process is exothermic and the sign of the heat of reaction is negative.
Let us now look at the reaction as shown, we can see that it involves the combustion or burning of glucose in oxygen. We now seek to obtain the correct equation for the combustion reaction.
Thus, we can now write effectively that the correct equation of the reaction is correctly written as ((6 mol)(-393.5 kJ/mol) + (6 mol)(-285.83 kJ/mol)) - (1 mol)(-1,273.02 kJ/mol).
Learn more about heat of combustion:https://brainly.com/question/14317568
#SPJ1
. The molar mass of aluminum is 26.98 g/mol and the molar mass of fluorine is 19.00 g/mol. Calculate the molar mass of aluminum trifluoride, AlF3.
Answer:
83.98 g/mol
Explanation:
To find the molar mass of AlF₃, you need to add the individual molar masses of each element times their quantities. For instance, since there are 3 fluorine atoms in AlF₃, the molar mass of AlF₃ must include the molar mass of fluorine times 3.
Molar Mass (Al): 26.98 g/mol
Molar Mass (F): 19.00 g/mol
Molar Mass (AlF₃): 26.98 g/mol + 3(19.00 g/mol)
Molar Mass (AlF₃): 83.98 g/mol
How is it possible to change electrical devices when the power is out?
(Please help!!)
Answer:
An uninterruptible power supply can save data during an outage, and a surge protector can prevent damage from a surge. Surge protectors absorb or ground overvoltage from spikes. Each time a surge protector does its job, resulting damage can reduce effectiveness for the next surge.
Explanation:
What is the chemical symbol?
Answer:
symbol is Al
Explanation:
aluminum is that element
please mark me brainliest
Which statement is always true about a reversible chemical reaction?
Answer:
It is a chemical reaction in which the reactants form products and products react together to give reactants back. That means reversible reactions can go in both directions forward as well as backward direction.
why are scientific methods important in the study of science
a.they are useful only for teaching students about science
b.they help scientists understand complex ideas and objects that arent easy to handle
c.they enable scientists to popularize their work in society
d.they are necessary to conduct the peer review process
e.they are necessary for turning a hypothesis into a law
Answer:rrrrrrrrrrrrrrrrrrr
Explanation:
rrrrrrrrrrrrrrrrrrrrrrrr
What pressure would 2.5 moles of N2 gas exerton the walls of a 10.0 L container at a temperature of 25 C (298 K)
Answer:
6.1 atm
General Formulas and Concepts:
Chemistry - Gas Laws
Combined Gas Law: PV = nRT
P is pressure in atmV is volume in Litersn is number of molesR is the gas constant: 0.0821 (L · atm)/(mol · K)T is temperature in KelvinsTemperature Conversion: K = °C + 273.15
Explanation:
Step 1: Define
n = 2.5 mol N₂
V = 10.0 L
T = 25 °C = 298.15 K
Step 2: Find Pressure P
Substitute: P(10 L) = (2.5 mol)(0.0821 (L · atm)/(mol · K)(298.15 K)Multiply: P(10 L) = 61.1953 L · atmIsolate P: P = 6.11953 atmStep 3: Check
We are given 2 sig figs as our lowest. Follow sig figs and round.
6.11953 atm ≈ 6.1 atm
The mitochondrial form of the PEPCK enzyme, with oxaloacetate as substrate, is a(n)__________enzyme for the Citric Acid Cycle
(a) inhibitory
(b) activatory
(c) anapleurotic
(d) catapleurotic
Answer:
(d) catapleurotic
Explanation:
Phosphoenolpyruvate carbokinase (PEPCK) is usually used in the conversion of oxaloacetate to phosphoenolpyruvate (an important intermediate in glycolysis and gluconeogenesis, C₃H₅O₆P). The main function of this catapleurotic enzymes is in the catalysis of the forward conversion of oxaloacetate to phosphoenolpyruvate.
What is the percent composition of nitrogen in sodium nitride
Answer:
16.86%
Explanation:
Na3N is sodium nitride.
% of N = mass of N/ molar mass of Na3N *100
% of N = 14/83*100= 16.86%
The percent composition of nitrogen in sodium nitride is 16.86%
What is sodium nitride?Sodium nitride is an inorganic compound that is used in preservatives and antidote for cyanide poisoning.
The molar mass of Na3N is 83 M
The mass of Na3N is 14 g
[tex]% \;of \;N = \dfrac{mass of N}{ molar mass of Na3N } \times 100[/tex]
[tex]\% \;of \;N = \dfrac{mass\; of \;N}{molar\; mass\; of\; Na3N} \times 100\\\\\\\% \;of \;N = \dfrac{14}{83} \times 100 = 16.86\%[/tex]
Thus, the percent composition of nitrogen in sodium nitride is 16.86%.
Learn more about sodium nitride
https://brainly.com/question/2596742
#SPJ2
What is the correct structure for 7-methyl-4-octanone?
Answer:
7-METHYL-4-OCTANONE 7-methyloctan-4-one 20809-46-5 4-Octanone, 7-methyl- 7-methyl-octan-4-one More...
Explanation:
PLEASE HELP A HOMIIE
Answer:
Its the first one. The cells are arranged for structure.
Explanation:
Animal cells do not need to maintain a shape since out bodies do it for us. Plant cells need something for structure.
Ions:
Ex: Aluminum has ___3___ valence electrons. It will ______lose 3__ electrons and become an ion with a _____3+_____ charge. (don’t just say + or -)
Chlorine (Cl) has 7 valence electrons. It will _____________ electron(s) and become an ion with a _____________ charge.
Iron (Fe) has 2 valence elecatrons. It will _____________ electron(s) and become an ion with a ______________ charge.
Sulfur (S) has _____________ valence electrons. It will ___________ electron(s) and become an ion with a ________________ charge.
Neon (Ne) has __________ valence electrons. Its valence shell is ___________ so it will neither __________ nor ___________ electrons. It will not become an ion and it will not bond with another atom. It is stable by itself.
Copper (Cu) has 1 valence electron. It will _____________electron(s) and become an ion with a __________ charge.
which letters of an air mass represents moisture content
Answer:
Explanation:
One that forms over the Indian Ocean is called a maritime tropical air mass and is warm and humid. Air masses are classified on weather maps using two or three letters. A lowercase letter describes the amount of moisture in the air mass: m for maritime (moist) and c for continental (dry).
The letter 'c' of an air mass represents moisture content.
What is an air mass?An air mass can be described as a volume of air defined by its humidity and temperature. Air masses are classified depending on latitude and their continental or maritime source regions. Warmer air masses are deemed tropical while Colder air masses are termed polar or arctic.
The maritime and monsoon air masses are moist while Continental and superior air masses are dry. When an air mass will move away from its source region, water bodies and underlying vegetation can quickly modify its character.
The first letter "c" represents its moisture properties in continental air masses (dry) while "m" represents maritime air masses. The letter "T" stands for Tropical, "A" stands for Arctic or Antarctic, "E" stands for Equatorial, "P" stands for Polar, "M" stands for monsoon, and "S" stands for adiabatically drying and warming air.
Learn more about air mass, here:
https://brainly.com/question/12089291
#SPJ2
The products of a combustion reaction include:
A: water and carbon dioxide
B: hydrogen, water, and carbon dioxide.
C: water and carbon monoxide.
D: hydrogen and water.
Answer:
A
Explanation:
Combustion reactions always produce water and CO2
The products for the combustion have been water and carbon dioxide along with the liberation of heat. Thus, option A is correct.
Combustion can be defined as the process of burning carbon-based compounds in the presence of oxygen. Combustion has been the process that liberates heat energy.
The combustion can be given as:
Hydrocarbon [tex]\rightarrow[/tex] Carbon dioxide + Water + Heat
The products for the combustion have been water and carbon dioxide along with the liberation of heat. Thus, option A is correct.
For more information about combustion, refer to the link:
https://brainly.com/question/9641392
When testing for hydrogen gas in the laboratory a glowing splint is inserted into the gas which results in a pop sound. What is associated with the formation of the pop sound?
A. physical change
B. chemical change
C. exothermic reaction
D. endothermic reaction
How many molecules are present in 187 grams of XeF4
There are 5.43 x 10²³ present in 187 grams of XeF₄
Further explanationThe mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
Moles can also be determined from the amount of substance mass and its molar mass
[tex]\tt n(mol)=\dfrac{mass(m)}{MW}[/tex]
mass of XeF₄ = 187 g
mol XeF₄ (MW=207,2836 g/mol) :
[tex]\tt mol=\dfrac{187}{207,2836 g/mol}=0.902[/tex]
Number of molecules :
[tex]\tt N=0.902\times 6.02\times 10^{23}\\\\N=5.43\times 10^{23}[/tex]
which of the following is the best definition for volume
a. solids are the only matter with volume
b. all energy has volume
c. volume is the three-dimensional size of an object
d. gases do not have volume
Answer:
C
Explanation:
I hope that helps!!! it kinda gave you the answer though
Indicate whether aqueous solutions of each of the following solutes will contain only ions, only molecules, or mostly molecules and a few ions:
a) NH4Cl, a strong electrolyte.
b) Ethanol, CH3-CH2-OH, a nonelectrolyte.
c) HCN, hydrocyanic acid, a weak electrolyte.
Answer:
Following are the solution to the given points:
Explanation:
In point a, the answer is only ions because of [tex]NH_4Cl[/tex] has a strong electrolyte.
In point b, the answer is the only molecules because of ethanol [tex]CH_3CH_2OH[/tex], it has a nonelectrolyte.
In point c, the answer is the few ions because of hydrocyanic acid HCN, which has a weak electrolyte.
(a) Only ions.
(b) Only Molecules.
(c) Few ions.
The explanation is as follows:(a) In this, only ions should be considered as it contains strong electrolyte.
(b) In this, only molecules should be considered as it contains non-electrolyte.
(c) In this, few ions should be considered due to hydrocyanic acid HCN, that contains weak electrolyte.
Therefore we can conclude that
(a) Only ions.
(b) Only Molecules.
(c) Few ions.
Learn more: brainly.com/question/17127206
A chemist accidentally leaves an open beaker containing 100.0 mL of a 0.400 M CuCl(aq) solution on a lab bench. They return a few days later to find that the volume of the solution has decreased to 30.0 mL. What is the molarity of this partially evaporated solution, assuming the solute does not evaporate? Give your answer to 2 decimal places.
Answer:
Me gusta el triángulo, la respuesta es triángulo.
Explanation:
can someone explain this better and simpiler?
Response:
Sorry but I think you forgot to attach or include something, thanks for the points tho!
Other:
Brainliest? Thanks!
The table below gives the numbers of protons, electrons, and neutrons in four atoms.
Atom Number of protons Number of electrons Number of neutrons
1 39 39 52
2 40 40 50
3 39 39 54
4 40 40 51
Based on the information that is given, which atom in the table has the highest mass?
1
2
3
4
Answer:
3. 39 39 54
Explanation:
Atoms are the smallest units of matter that have the characteristics of a chemical element. They consist of small particles called protons, electrons, and neutrons.
Protons are positively charged particles that make up the nucleus of the atom along with neutrons, neutrally charged particles. Their mass is almost the same - about 1 AMU (atomic mass unit). Electrons, the negatively charged particles, are much lighter than them and don't significantly contribute to the mass of the atom. Their mass is equal to about 1/2000 of the mass of a proton or neutron.
This is why we need to determine which atom out of the ones you were given has the highest number of protons and neutrons. The first has 91, the second 90, the third 93, and the fourth 91. This means that the third atom has the highest mass.
Calculate the molarity of the two solutions.
The first solution contains 0.350 mol of NaOH in 1.05 L of solution.
molarity:
The second solution contains 14.3 g of NaCl in 879 mL of solution.
molarity:
1. 0.33 M
2. 0.278 M
Further explanationMolarity is a way to express the concentration of the solution
Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution
[tex]\large{\boxed {\bold {M ~ = ~ \frac {n} {V}}}[/tex]
Where
M = Molarity
n = Number of moles of solute
V = Volume of solution
1. 0.350 mol of NaOH in 1.05 L of solution.
n=0.35
V=1.05 L
Molarity :
[tex]\tt M=\dfrac{0.35}{1.05}=0.33[/tex]
2. 14.3 g of NaCl in 879 mL of solution.
mol NaCl(MW=58.5 g/mol) :
[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{14.3~g}{58.5~g/mol}=0.244[/tex]
Molarity :
[tex]\tt M=\dfrac{0.244}{0.879~L}\\\\M=0.278[/tex]
Name the group of elements that will not participate in ionic bonding.
Alkali Metals
Alkaline Earth Metals
Transition Metals
Halogens
Noble Gases
Answer:
Noble Gases
Explanation:
Noble gases are very unreactive because they already have a full valence shell and therefore, do not need to bond.
Answer:
Noble gases
Explanation:
List down 10 different types of minerals (metallic and non metallic) include the different uses and help in the economy of these minerals.
Answer:
names of 10 metallic minerals are Silver, Chromium, Tin, Nickel, Copper, Iron, Lead, Aluminum, Gold, and Zinc.
Explanation: