Which statement describes proper conduct in the laboratory?
Select one:
O a. Eating snacks in the laboratory is allowed.
O b. In order to identify things they should be tasted.
O c. Colorless fumes should be identified by direct smelling.
O d. Be aware of the location of safety and first aid equipment.
Answer:
D.
Explanation:
I mean. It's logic for sure
Answer:
Its D and pls mark brainliest
Explanation:
लेख्नुहोस् । (Deserts are very hot during the day and very cold
during the night. Give reason.)
Because deserts have such little water vapor in the air, it makes it harder to trap heat or cold in a desert. And at night, the sun no longer heats the desert and the heat from the day doesn't stay trapped. Because of this, some deserts can get extremely cold at night, dropping to temperatures below 40F.
Hope this helps!! Have a wonderful day!!
It is actually sand, which turns the entire phenomenon hot. Sand cannot hold the heat. It acts like a mirror to the sun. During the daytime, it stays warm, and when the Sun is absent it loses all its heat making the nights colder. There’s nothing in the desert that can either absorb heat from the sun or hold it on the surface when the sun is set.
Work=? time=5s Power = 40w
Answer:
200 J
Explanation:
Work = Power x time
Work = (40w)(5s)
Work = 200 J
The diagram below shows four coastline locations on Earth with respect to the moon at a given time. Moon A B D C In this current position, which coastline(s) are experiencing a daily high tide? Only A O Only B O Both A and C Both B and D
Answer: Only A
Explanation: The moon controls the tides because of its gravitational pull. The moon's gravitational pull is weaker than Earths that is why the moon's gravitational pull only effectts water on the earth.
____________ is refining the extracted raw metals into a purest form
Answer:
Extractive metallurgy
Explanation:
Extractive metallurgy is the practice of removing valuable metals from an ore and refining the extracted raw metals into a purer form.
please answer thx will mark brainliest if correct
Answer:
C
Explanation:
Gases have lowest forces of attraction.
Una solución hallar punto de vista física y punto de vista químico (sal) 50g de sal y 250 ml de agua hallar %m/m %m/v molalidad, molaridad, fracción molar del soluto y del solvente
Answer:
% m/m = 16.6%
% m/v = 20%
3.42 m (molalidad)
3.42 M (molaridad)
Fraccion molar del soluto = 0.06
Fraccion molar del solvente = 0.94
Explanation:
Nuestra solución está compuesta por:
Soluto: 50 g de sal
Solvente: 250 mL de agua.
%m/m %m/v molalidad, molaridad, fracción molar del soluto y del solvente son distintas formas de definir la concentración:
% m/m son los gramos de soluto cada 100 g de solución.
No sabemos la masa de solución pero con la densidad del agua (solvente), sabemos que los 250 mL contienen 250 gramos de solvente. (Densidad del agua 1g/mL). En conclusión, la masa de solución es 50 g + 250g = 300
% m/m = (50g /300g ) . 100 = 16.6%
Vamos a definir que el volumen de la solución es igual al del solvente: 250 mL.
% m/v = la masa de soluto, cada 100 mL de solución
= (50 /250) . 100 = 20 %
Molalidad, son los moles de soluto por cada kg de solvente.
Convertimos gramos a kg → 250 g . 1kg /1000g = 0.25kg
Convertimos la masa de soluto (sal) a moles.
NaCl → 50 g . 1mol/ 58.45g = 0.855 moles
m = 0.855 /0.25 → 3.42 m (molalidad)
Molaridad son los moles de soluto por cada L de solución.
Convertimos mL a L → 250 mL . 1kg / 1000mL = 0.25 L
sabiendo que los moles de soluto son 0.855, en este caso la molaridad es igual a la molalidad ( 3.42 M)
Para calcular la fracción molar, necesitamos moles de soluto y de solvente.
Ya contamos con los moles de soluto.
Moles de solvente: 250 g . 1mol /18g = 13.89 mol
Moles totales = 0.855 + 13.89 = 14.745
Fracion molar del soluto: (0.855/ 14.745) = 0.06
Fraccion molar del solvente: (13.89 / 14.745) = 0.94
Suppose you are designing a heat exchanger to remove energy from a motor as quickly as possible. Energy will be transferred from the motor to the heat exchanger. Then the energy will be transferred from the heat exchanger to the air. The table shows the thermal conductivities of a few substances as measured in W/m·K. The greater the thermal conductivity, the faster the rate of energy transfer. Which material would be the best choice?
a: copper
b: glass
c: steel
d: polystyrene
What is simple chemical test could you carry out to see if carbon dioxide has been produced
Carbon Dioxide
A positive test will result in the lime water turning milky. Lime water turns milky as the Calcium hydroxide (chemical name for limewater) reacts with carbon dioxide to form Calcium Carbonate which is insoluble in water and thus forms a milky white precipitate.
How many grams of sulfur trioxide are required to produce 2.00 mol of sulfuric acid in an
excess of water?
CH3OH can be synthesized by the reaction:
CO(g) + 2 H20) — CH3OH)
What volume of CH3OH gas (in L) can be synthesized if 18.6 L of Hy gas completely reacts at STP conditions?
Answer:
5
Explanation:
A sample of hydrogen gas has a volume of 145 mL when measured at 44
degrees C and 1.47 atm. What volume would the hydrogen sample occupy
at STP?
Answer:
[tex]186.01\ \text{mL}[/tex]
Explanation:
[tex]P_1[/tex] = Initial pressure = 1.47 atm
[tex]P_2[/tex] = Final pressure = [tex]10^5\ \text{Pa}[/tex]
[tex]T_1[/tex] = Initial temperature = [tex]44^{\circ}\text{C}[/tex]
[tex]T_2[/tex] = Final temperature = [tex]273.15\ \text{K}[/tex]
[tex]V_1[/tex] = Initial volume = 145 mL
[tex]V_2[/tex] = Final volume
We have the relation
[tex]\dfrac{P_1V_1}{T_1}=\dfrac{P_2V_2}{T_2}\\\Rightarrow V_2=\dfrac{P_1V_1T_2}{T_1P_2}\\\Rightarrow V_2=\dfrac{1.47\times 101325\times 145\times 273.15}{(44+273.15)\times 10^5}\\\Rightarrow V_2=186.01\ \text{mL}[/tex]
Final volume of the sample is [tex]186.01\ \text{mL}[/tex].
⚠️NO LINKS⚠️(it will get reported)
In a lab, students measured the mass of an unknown metal to be 46.4 g. The metal sample releases 769 J when it is cooled from 101.0°C to 30,00 °C, the
metal is most likely
Lead
. Copper
Mercury
Silver
Answer:
I'm thinking cooper but not sure
HELP ASAP!!!
WAVES ALWAYS ORIGINATE WITH SOME
a
person
b
object
C
disturbance
Answer:
Disturbance
Explanation:
I believe it is Disturbance because waves are normally caused by wind, and wind classifies as Disturbance.
what are items that are ferromagnetic material
Answer:
I'll give you three examples:
Iron
Cobalt
Nickel
N2(g) + 2 O2(g) → 2 NO2(g)
Answer
Answer:
180.6
Explanation:
N2 (g) + 2O2 (g) → 2NO2 (g) ΔH = 66.4 kJ
2NO (g) + O2 (g) → 2NO2 (g) ΔH = -114.2 kJ
Hope this helped, and please mark as Brainliest :)
0 Which is not a chemical change?
A Iron combines with oxygen to form
rust.
B Wax melts as it absorbs heat from a
flame.
C Pure sodium explodes when dropped
in water.
D Glucose molecules are produced in a
plant leaf.
Answer:
B, wax melting
Explanation:
When wax melts, the form of matter is the only thing that changes. Wax in this case goes from a solid to a liquid, and this process can be reversed when it cools. Hence labeling it a physical change instead.
solid sodium chloride is dissolved in water. the sodium chloride solution is electrolysed in the apparatus. state why sodium chloride solution , rather than solid chloride must be used in this experiment.
Answer: water solutions conducts charge
Explanation: solid sodium chloride is n insulator.NaCl is dissolved in water
In ionic forms. In solution there are Na+ and Cl- ions which can transfer charge.
Ralph's friend invited him to attend a hard rock concert. Ralph did not want to go because he assumed other people who attended would be aggressive and unruly. Ralph's attitude is BEST described as an example of
prejudice
ambiguity
nonconformity
discrimination
impression formation
Answer:
Prejudice
Explanation:
Answer: your answer would be prejudice.
32)
In some water purification plants, solid matter is skimmed off the top of the water. This is separating a mixture by what method?
A)
chromatography
B)
evaporation
floatation
D)
sifting
CH4O+ O2 → CO2 + H2O
Balance the following chemical equation
Answer:
2 CH4O + 3 O2 = 2 CO2 + 4 H2O
What are the controlled, independent, and dependent variables in a basic density column experiment?
WILL MAKE BRAINLIEST
Answer:
The Independent Variable is what we change or control in the experiment. The Dependent Variable is what we are testing and will be measured in the experiment. The Control Variables are what we keep the same during the experiment to make sure it's a fair test. hope this helps =)
Explanation:
HURRY ILL GIVE BRAINLIEST!
Match the cause to its effect.
Answer:
Cattles are giving nutrition supply throughout the year----some animals require nutrient enhancement for health
calves are given colostrum at birth----newborns require antibodies from their mothers
I dont want to write, so you know what the last option is
Explanation:
:) hope this helps
✓ What kind of carbon storages would be the most affected by humans?
Answer: Burning fuels?
Explanation: I’m not very sure actually
The complete
conversion of 90.0
grams of hydrogen to
ammonia would require
how many moles of
nitrogen gas?
Answer:
15moles
Explanation:
The balanced equation of this reaction is as follows:
N2 + 3H2 → 2NH3
Molar mass of H2 = 2g/mol
mole = mass/molar mass
mole = 90/2
mole = 45moles.
Based on the above balanced equation, 1 mole of nitrogen gas (N2) reacts with 3 moles of hydrogen gas (H2)
Hence, 45moles of hydrogen gas will produce (45 × ⅓) = 15moles of nitrogen gas (N2).
Answer:
Its 14.9 for those who are doing the escape room :)
Explanation:
1. You have 3.5L of a gas at 6 atm of pressure. The pressure drops to 2.4 atm, what is the new volume of
the gas?
I
Answer:
8.75 LExplanation:
The new volume can be found by using the formula for Boyle's law which is
[tex]P_1V_1 = P_2V_2[/tex]
Since we're finding the new volume
[tex]V_2 = \frac{P_1V_1}{P_2} \\[/tex]
We have
[tex]V_2 = \frac{3.5 \times 6}{2.4} = \frac{21}{2.4} \\ = 8.75[/tex]
We have the final answer as
8.75 LHope this helps you
ennolno nsr svi5691 som i 1sq0o
The copper chloride solution used in the investigation contained 300 grams per dm of
solid CuCl2 dissolved in 1 dm of water.
The student used 50 cm of copper chloride solution in each experiment.
Calculate the mass of solid copper chloride used in each experiment.
[3 marks]
if 3.75 moles of LiCl is added to 72.7 ml of water, what is the molarity?
Why is nuclear fusion not used to produce electricity?
O A. Fusion requires conditions that exist only in the cores of stars.
B. Fusion produces nuclear waste.
C. Fusion requires steam turbines, which are expensive.
D. Fusion produces only a small amount of energy.
Answer: A is correct for ape.x
Explanation:
Nuclear fusion not used to produce electricity because fusion requires conditions that exist only in the cores of stars. Hence option A is correct.
What is nuclear fusion?Nuclear fusion is defined as the process that produces a single heavier atomic nucleus from the union of two lighter ones while releasing enormous quantities of energy. Controlled atom fusion generates around four million times as much energy as controlled nuclear fission and chemical processes like burning coal, oil, or gas.
Normal electrostatic interactions between positively charged nuclei prohibit them from coming close enough to collide and allow fusion to happen, hence fusion is not feasible. Fusion might be used to generate electricity economically if there was a sufficiently big and sustained energy "profit".
Thus, nuclear fusion not used to produce electricity because fusion requires conditions that exist only in the cores of stars. Hence option A is correct.
To learn more about nuclear fusion, refer to the link below:
https://brainly.com/question/12701636
#SPJ2
Which are different structures of the eye? Select four options.
please help !!!!!!!!
pupil
cochlea
cornea
auricle
retina
lens
Answer:
Pupil, Cornea, Retina, and Lens
Explanation: