PLS HELP ASAP NO LINKS
What type of scientist studies matter and its composition?
Biologist
Chemist
Physicist
Engineer
Answer:
.biology and maybe physics
Answer:
Biologist
ExplanationBiologist Unlike the above type of scientist, geoscientists’ work involves exploring the earth and its internal environment. They study the composition, structure, and processes of the earth by being indoors and outdoors. They contribute to the discovery of mines, petroleum deposits, minerals, and other aspects of the earth.
How many moles of KCl are produce when 61.5 g of KClO3 are decomposed?
Answer:
0.502mol
Explanation:
The balanced chemical equation of the reaction described in this question is as follows:
2KClO3 → 2KCl+ 3O2
According to the equation above, 2 moles of KClO3 will produce 2 moles of KCl.
Using mole = mass/molar mass to convert mass of KClO3 to moles
Molar mass of KClO3 = 39 + 35.5 + 16(3)
= 39 + 35.5 + 48
= 122.5g/mol
mole = 61.5 g ÷ 122.5g/mol
mole = 0.502mol
Since 2 moles of KClO3 will decompose to produce 2 moles of KCl.
0.502 mol of KClO3 will decompose to produce 0.502 × 2/2
= 0.502mol of KCl.
Select the correct answer.
A circuit is used in which process?
OA. electricity
OB. magnetism
OC. velocity
OD. gravity
Answer:
electricity
Explanation:
A circuit is used in every electrical and electronics operation.
Which product is made from nonmetallic mineral resources?
a. Stainless steel
b. iron nails
c. Copper wires
d. concrete
Answer:
Concrete
Explanation:
Which wave is used to identify the heat given off by distant objects in space
Convert 6.71 moles NH3 to number of molecules.
Answer: There are [tex]40.41 \times 10^{23}[/tex] molecules present in 6.71 moles of [tex]NH_{3}[/tex].
Explanation:
Given: Moles of [tex]NH_{3}[/tex] = 6.71 mol
According to the mole concept, 1 mole of every substance contains [tex]6.022 \times 10^{22}[/tex] molecules.
Therefore, molecules present in 6.71 moles are calculated as follows.
[tex]Molecules = moles \times 6.022 \times 10^{23}\\= 6.71 \times 6.022 \times 10^{23}\\= 40.41 \times 10^{23}[/tex]
Thus, we can conclude that there are [tex]40.41 \times 10^{23}[/tex] molecules present in 6.71 moles of [tex]NH_{3}[/tex].
What type of wave has the SHORTEST wavelength and the highest frequency?
Answer:
The answer is gamma rays.
Explanation:
Gamma rays have the highest energies, the shortest wavelengths, and the highest frequencies on the electromagnetic spectrum.
in your notebook,write the appropriate tempo for the following actions.Then demostrate the actions then,demostrate the action in front of your parents,guardian
Answer:
cell :—
•They lack a well-defined nucleus, have a nucleoid instead.
•Usually have double-stranded, circular DNA.
•Do not have mitochondria.
Eukaryotic cell :—
•Have a well-defined nucleus enclosed in the nuclear membrane.
•Have a linear double-stranded nucleus.
•Mitochondria are present.
Three students measured the volumes of a pebble whose accepted volume is 2.71 cm3. Which list represents both accurate and precise:
A: 2.60 mL, 2.60 mL, 2.59 mL, 2.59 mL
B: 2.70 mL, 2.69 mL, 2.71 mL, 270 mL
C: 2.75 mL, 2.74 mL, 2.64 mL, 2.71 mL
D: A and B
Answer:
C
Explanation:
A mass of 68.45 g of nickel (II) sulfate hydrate, NiSO4∙ nH2O, loses 28.40 g upon dehydration. What is the hydration number of this compound? (Find n.)
Answer:
n=4
Explanation:
n= (154.75×28.40)÷(68.45×18)
n=3.5
n=4(approximately)
How much heat, in kilojoules, is needed to raise the temperature of 236 g of silver from 8.5oC to 34.9 °C? (cAg = 0.24 J/g°C)
Answer:
1.49kJ
Explanation:
Using the formula as follows;
Q = m × c × ∆T
Where;
Q = amount of heat (joules)
m = mass (g)
c = specific heat of silver (J/g°C)
∆T = change in temperature (°C)
According to the information given in this question;
mass of Silver (Ag) = 236g
c of Ag = 0.24 J/g°C
initial temperature (T1) = 8.5°C
final temperature (T2) = 34.9°C
∆T = T2 - T1 = 34.9 - 8.5 = 26.4°C
Using Q = m × c × ∆T
Q = 236 × 0.24 × 26.4
Q = 1,495.3 Joules
Amount of heat needed to raise the temperature of Silver (Q) in kilojoules is 1495.3/1000 = 1.4953
Q = 1.49kJ
The pH of a solution is 8. Some hydrochloric acid is added to the solution. Suggest the pH of the solution after mixing. pH=.......??
Answer:
Probably around 6 because the ph of hydrochloric acid is 3
Explanation:
5) How many Kilograms are in 12 L of Chlorine Gas?
Answer: 0.03798 kilograms
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given volume}}{\text {Molar Volume}}=\frac{12L}{22.4L}=0.535moles[/tex]
1 mole of chlorine gas [tex](Cl_2)[/tex] weighs = 71 g
Thus 0.535 moles of chlorine gas [tex](Cl_2)[/tex] will weigh = [tex]\frac{71}{1}\times 0.535=37.98g=0.03798kg[/tex] (1kg=1000g)
Thus there are 0.03798 kilograms in 12 L of chlorine gas.
Which procedure is an attempt to correct a genetic disorder by replacing a mutated gene with a normal allele?
O selective breeding
• cloning
O artificial selection
•
gene therapy
gene therapy
Explanation:
Gene therapy, also called gene transfer therapy, the introduction of a normal gene into an individual's order to repair a mutation that causes a genetic disease.
Answer:
C artificial selection
Explanation:
Brainly please
Which example in the video is a physical change?
A) Burning steel wool
B) Mixing chemicals
C) Rusting nail
D) Melting ice cream
D melting ice cream because if u know what a physical change is its a change that you can reverse chimical change are changes you cant reverse so u can freeze back ice cream so :D
If 125 mL of 0.56 MH2SO4, is diluted to a volume of 0.250 L, what is the molarity of the resulting solution?
Answer:
0.28M H2SO4
Explanation:
The molarity of a solution is defined as the ratio between the moles of the solute (In this case, H2SO4) and its volume in liters.
In the problem, the volume of the solution is increased from 125mL to 250mL. That means the solution is diluted:
250mL / 125mL = 2 times.
As the solution is diluted 2 times, the concentration is decreased in 2, that is:
0.56M / 2 =
0.28M H2SO4. Water is one of our most important resources. Only about 1% of the Earth's water is for human needs. Name four ways you can help conserve water. This is for science btw...
Answer:please see explanation for answers
Explanation:
Water conservation is an approach geared towards controlling how water is used. Because of the ever growing population, which weighs so much on water available to mankind,Over negligence and abuse of our water resources have been a great point of concern, that is why the need for the knowledge of water conservation is preached.
Now, some of the ways we can conserve water include
1. Putting off taps while lathering the hands with soap
2.use of irrigation system to water crops and plants
3.. while brushing, make sure to turn off the tap or faucet
4. use a shower rather than a bath
Beryllium hydrogen carbonate is more than 3% hydrogen by mass.
True
False
Why is carbon dioxide a covalent bond?
Explanation:
One atom of carbon (2.4) combines with two atoms of oxygen (2.6) to form the compound carbon dioxide CO2 (only the outer shell of carbon's electrons are shown). ... The carbon dioxide molecule is held together by the strong C=O. carbon–oxygen double covalent bonds by sharing electrons.
How many atoms are there in 6.8g of S?
What is the single replacement reaction of Zinc + Lead(iv) Chloride
Answer:
[tex]2Zn+PbCl_4\rightarrow 2ZnCl_2+Pb[/tex]
Explanation:
Hello there!
In this case, when referring to single replacement reactions, it is crucial for us to figure out the formula of the starting reactants; thus, we know zinc is Zn and lead (IV) chloride is PbCl₄. In such a way, the reaction proceeds as follows:
[tex]Zn+PbCl_4\rightarrow ZnCl_2+Pb[/tex]
Which must be balanced as shown below:
[tex]2Zn+PbCl_4\rightarrow 2ZnCl_2+Pb[/tex]
Regards!
State the trend in chemical reactivity as we go down the group for Group I elements Account for
this trend using the electronic structures of the elements.
Answer: The reactivity of group 1 elements increases as you go down the group because: the atoms become larger. the outer electron becomes further from the nucleus. the force of attraction between the nucleus and the outer electron decreases.
Why do you think certain countries favored military solutions to the great depression while other contries did not
Answer:
The answer is below
Explanation:
Certain countries like Germany under Adolf Hitler favored military solutions to the great depression because the government felt that having a mass production of military weapons and recruitment of unemployed people or citizens into the army would change the dire situation.
On the other hand, countries like the United States did not favor the military solutions but instead choose the NEW DEAL under Franklin D Roosevelt; the reason could be linked to their democratic culture, the isolation belief tendency.
The first organisms to arrive in an ecosystem?
water, soil, temperature, space
Answer:
wdym??
Explanation:
Answer:
wdym by water, soil, temperature, space?
what will litmus paper turn when it reacts with sodium nitrate?
PLEASE HELP
Referring to the energy diagram below which arrow segment represents the activation
energy of this reaction?
O Arrow B
O Arrow D
O Arrow A
O Arrow C
Answer:
Arrow B
Explanation:
What are carbohydrates?
A. a type of base
B. a type of glyceride
C. a type of macromolecule
D. a type of amino acid
Answer:
a
Explanation:
me say so
Answer:
C
Explanation:
If you stay at 90 degrees Celsius and a gas in a liquid solution has a pressure of 2 atm, what solubility should it have if it has a solubility of 64 g/L at a pressure of 8 atm?
Answer:
im not sure
Explanation:
How many formula units are in 325 grams of iron (III) chloride?
Answer:
1.204 × 10^24 formula units
Explanation:
Using the following formula to convert mass of iron (III) chloride to moles;
mole = mass/molar mass
Molar mass of FeCl3 = 56 + 35.5(3)
= 56 + 106.5
= 162.5g/mol
Mole = 325/162.5
mole = 2mol
Next, to calculate the formula units of FeCl3, we multiply the number of moles of FeCl3 by Avagadro number (6.02 × 10^23)
Formula units of FeCl3 = 2 × 6.02 × 10^23
12.04 × 10^23
= 1.204 × 10^24 formula units.