Answer: Disposable gloves should be put on before handling any glassware or chemicals for the experiment for work in the lab.
Explanation:
Disposable gloves are helpful in protecting skin of a person from coming in direct contact with chemicals.
As a result, it is important to wear disposable gloves before handling any glassware or chemicals for carrying out an experiment.
Thus, we can conclude that disposable gloves should be put on before handling any glassware or chemicals for the experiment for work in the lab.
Michael is studying the factors that affect corrosion of metals. He wants to test the effect that different concentrations of an acid will have on the corrosion of a metal. As he sets up and completes his experiment, which of the following experimental designs would be most likely to help him answer his question? A. Allow several metal samples to soak in different amounts of acid of a single concentration and then measure the amount of corrosion on each. B. Prepare solutions of different acid concentrations, measure 50 milliliters of each into different beakers, and place metal samples of different types but of the same mass into the beakers. C. After allowing several small metal sheets to be exposed to different acid concentrations, measure the surface area of each that is corroded. D. After allowing a small metal sheet to be exposed to one acid concentration, place it in different acid concentrations, then measure the surface area that is corroded.
Answer:
B. Prepare solutions of different acid concentrations, measure 50 milliliters of each into different beakers, and place metal samples of different types but of the same mass into the beakers.
Explanation:
Since Michael is studying the factors that affect corrosion of metals, and wants to test the effect that different concentrations of an acid will have on the corrosion of a metal, using different acid concentrations of the same volume on different metal samples of the same size would give a much better than all the other options because, a standard volume of acid is used and also a standard mass of metal is used. So, the effect can be measured quantitatively since we have the same quantity of sample.
So, option B is the answer
Barbara is conducting an experiment to observe heat flow. She places one piece of metal in a freezer at -18 degrees Celsius (°C) and a second piece of metal in an oven at 200 °C. After 2 hours, she takes the metal pieces out of the freezer and oven and places them both in the same beaker of boiling water for two minutes. Which of the following best describes how some of the heat will initially move in this system?
Heat will flow from the frozen metal into the hot metal.
Heat will flow from the boiling water into the hot metal.
Heat will flow from the boiling water into the frozen metal.
Heat will flow from the frozen metal into the boiling water.
Answer: The correct answer is heat will flow from the boiling water into the frozen metal.
Explanation:
According to the law of conservation of energy, energy cannot be destroyed nor created but it can be transformed from 1 form to another form.
There are 3 processes of heat transfer:
Conduction: This type of heat transfer occurs when there is direct contact between the two objects.Convection: This type of heat transfer occurs when there is a movement of fluid (liquid or gas) due to the movement of hot layers to the top and cold layers to the bottom which leads to convection currents. Radiation: This type of heat transfer occurs when there is a direct transfer of energy through space.The heat moves from a hot surface to a cold surface to maintain equilibrium.
We are given:
A metal is placed in a freezer (cold object) and another metal is placed in an oven (hot object) and then both the metals are placed in boiling water.
Initially, the heat will flow from the boiling water (hot object) into the frozen metal (cold object) to maintain equilibrium
Hence, the correct answer is heat will flow from the boiling water into the frozen metal.
Which of these is not a mixture?
A) Salt
B) Cooking oil
C) Tea leaves
D) Milk
ty
Answer:
the answer is salt because it has a uniform and definite composition
Explanation:
PLZ HELP!!! What mass of [tex]SrF_{2}[/tex] can be prepared from the reaction of 10.0g [tex]Sr(OH)_{2}[/tex] with excess HF? THANK U!!
Answer:
Approximately 10.5g or 10.4g [tex]SrF_{2}[/tex]
The radiostope radon 222 has a half life of 3.8 days. How much of a 73.9-g sample or radon 222 wouppd be left after 23 days ?? pls show an equation
Answer:
Is there a picture for it
Explanation:
because it would be a hard
A hydrocarbon contains 92.24 % carbon by mass and has a molar
mass of 78.12 g mol-1.
Determine the empirical formula and molecular
formula of the hydrocarbon
Explanation:
so for this one you know 92.24 is the mass of C so to work out the mass of hydrogen u so 100-92.24=7.76
so
C : H
92.24/12 : 7.76 /1
7.68 : 7.76
so 7.76÷7.68=1.01
so CH
12+1=13
78.12÷13=6.009
so CH×6= C6H6
hope this helps:)
Given 7 moles of nitrogen gas, how many moles of ammonia can you make?
Explanation:
just use the molar ratios to figure it out. Notice, you have to balance the chemical equation.
What is a balanced nuclear equation for the alpha decay of Strontium-90?
Answer: The balanced nuclear equation for the alpha decay of Sr-90 is [tex]_{38}^{90}\textrm{Sr}\rightarrow _{36}^{86}\textrm{Kr}+_2^4\alpha[/tex]
Explanation:
A nuclear reaction is defined as the reaction in which the changes in the nucleus of an atom take place and usually form a different element. The types of decay processes are:
Alpha decayBeta-decayGamma decayAlpha decay is the process in which a heavy nucleus decays into a light nucleus with the release of an alpha particle. This alpha particle carries a charge of +2 units and has a mass of 4 units. It is also known as the helium nucleus. The general equation for this decay process is:
[tex]X_Z^A\rightarrow Y_{Z-2}^{A-4}+\alpha _2^4[/tex]
The nuclear equation for the alpha decay of strontium-90 isotope follows:
[tex]_{38}^{90}\textrm{Sr}\rightarrow _{36}^{86}\textrm{Kr}+_2^4\alpha[/tex]
What makes radioisotopes useful for dating objects?
O A. They have unique emission spectra.
O B. They decay at a predictable rate.
C. Their decay products are easy to detect.
O D. They all have extremely long half-lives.
Answer:A
Explanation:
Option D. They all have extremely long half-lives makes radioisotopes useful for dating objects.
What are radioisotopes?Radioisotopes exist as radioactive isotopes of an element. They can also be described as atoms that include an unstable combination of neutrons and protons, or surplus energy in their nucleus.
A radionuclide exists as a nuclide that contains excess nuclear energy, causing it unstable. This excess energy can be utilized in one of three methods: emitted from the nucleus as gamma radiation; assigned to one of its electrons to terminate it as a conversion electron; or utilized to create and emit a unique particle from the nucleus.
Radioactive isotopes of radium, thorium, and uranium, for example, exist found naturally in rocks and soil. Uranium and thorium also happen in trace amounts in water. Radon, induced by the radioactive decay of radium, stands present in the air.
Hence, Option D. They all have extremely long half-lives makes radioisotopes useful for dating objects.
To learn more about radioisotopes refer to:
https://brainly.com/question/18640165
#SPJ2
ELECTRICITY IS ALLOWED TO PASS THROUGH ACIDIFIED WATER USING THE FOLLOWING EXPERIMENTAL SETUP.
QUESTION: IDENTIFY THE PROCESS
Answer: Electrolysis is passing an electric current through a liquid containing ions so that decomposition reaction takes place.
Electrolysis is passing an electric current through a liquid containing ions so that decomposition reaction takes place.When an electric current is passed through acidified water, it decomposes to give hydrogen and oxygen gas. The hydrogen gas is obtained at the cathode and the oxygen gas is obtained at the anode.
Electrolysis is passing an electric current through a liquid containing ions so that decomposition reaction takes place.When an electric current is passed through acidified water, it decomposes to give hydrogen and oxygen gas. The hydrogen gas is obtained at the cathode and the oxygen gas is obtained at the anode.The reaction for decomposition of water into oxygen and hydrogen is as follows:
Electrolysis is passing an electric current through a liquid containing ions so that decomposition reaction takes place.When an electric current is passed through acidified water, it decomposes to give hydrogen and oxygen gas. The hydrogen gas is obtained at the cathode and the oxygen gas is obtained at the anode.The reaction for decomposition of water into oxygen and hydrogen is as follows:2H2O(l) -------> 2H2(g) + O2(g)
What factor makes it possible for animals with endoskeletons to grow larger than animals with exoskeletons?
A. Endoskeletons can be removed and replaced.
B. Endoskeletons are lighter than exoskeletons.
C. Endoskeletons are made of fluid-filled tubes.
D. Endoskeletons lack joints that can break down.
i need help
Look at the activity series and select which two of the following reactions would happen on their own. (Remember, if the lone element is more active than the metal in the compound, the lone element will react and replace the metal in the compound.) Lithium (Li)
Potassium (K)
Calcium (Ca)
Sodium (Na)
Aluminum (Al)
Zinc (Zn)
Iron (Fe)
Tin (Sn)
Lead (Pb)
(Hydrogen) (H)
Copper (Cu)
Silver (Ag)
Gold (Au)
A.
2Li + ZnBr2 ->2LiBr + Zn
B.
Al + 3LiCl ->AlCl3 + 3Li
C.
Sn + ZnSe ->SnSe + Zn
D.
3Ca + Al2O3 ->2Al + 3CaO
Answer:
2Li + ZnBr2 ->2LiBr + Zn
3Ca + Al2O3 ->2Al + 3CaO
Explanation:
Spontaneous reactions are reactions that can happen on their own. For a spontaneous reaction to occur, a metal that is higher in the activity series must displace a metal that is lower in the activity series from its solution and not vice versa.
If we look at the two reactions selected in the answer, lithium is above zinc in the activity series and calcium is above aluminum in the activity series hence the two reactions occur spontaneously.
Matter takes up _____.
(a) Space and temperature
(b) Space and heat
(c) Space and mass
(d) Heat and temperature
The strength of the gravitational attraction depends on the mass of the objects involved and the distance between them. The gravitational force between two objects will be lowest in which of the following situations?
A. Both objects have small masses and are close together.
B. One object has a large mass, and the objects are close together.
C. Both objects have large masses and are close together.
D. Both objects have small masses and are far apart.
Answer:
d sguro
Explanation:
I'm not sure kung ayan ba
Which equation represents the correct net ionic equation for the reaction between Ca(OH)2 and H2SO4?
Upper H superscript plus, plus upper O upper H superscript minus right arrow upper H subscript 2 upper O.
2 upper H superscript plus, plus 2 upper O upper H superscript minus right arrow upper H subscript 2 upper O.
Upper C a superscript 2 plus, plus 2 upper O upper H superscript minus, plus upper S upper O subscript 4 superscript 2 minus right arrow upper C a superscript 2 plus, plus upper S upper O subscript 4 superscript 2 minus, plus 2 upper H subscript 2 upper O.
Upper C a (upper O upper H) subscript 2 plus upper H subscript 2 upper S upper O subscript 4 right arrow upper C a upper S upper O subscript 4 plus 2 upper H subscript 2 upper O.
Answer: The correct net ionic equation for the reaction is [tex]2H^{+}(aq)+2OH^{-}(aq)\rightarrow 2H_2O(l)[/tex]
Explanation:
Net ionic equation is defined as the equations in which spectator ions are not included.
Spectator ions are the ones that are present equally on the reactant and product sides. They do not participate in the reaction.
The balanced molecular equation is:
[tex]Ca(OH)_2(aq)+H_2SO_4(aq)\rightarrow CaSO_4(aq)+2H_2O(l)[/tex]
The complete ionic equation follows:
[tex]Ca^{2+}(aq)+2OH^-(aq)+2H^+(aq)+SO_4^{2-}(aq)\rightarrow 2Ca^{2+}(aq)+SO_4^{2-}(aq)+H_2O(l)[/tex]
As calcium and sulfate ions are present on both sides of the reaction. Thus, they are considered spectator ions.
The net ionic equation follows:
[tex]2H^{+}(aq)+2OH^{-}(aq)\rightarrow 2H_2O(l)[/tex]
Hence, the correct net ionic equation for the reaction is [tex]2H^{+}(aq)+2OH^{-}(aq)\rightarrow 2H_2O(l)[/tex]
Answer:
B. no reaction
Explanation:
How many moles are equal to 3.0x10^23 atoms of germanium? PLS ANSWER WITH WORK!
How does radon move up through rock and soil?
How many neutrons does this atom have?
4
6
10
14
Answer:
6
Explanation:
Electrons are floating around, and protons are outside of the nucleus center. The ones in the center are neutrons. I hope this helps.
I have a exam please answer fast
Answer:
C
[tex] \triangle \: H {}^{ \theta} _{s} = lattice \: energy + hydration \: energy \\ = + 2526 + ( - 2003 + (2 \times - 340)) \\ + 2526 - 2683 \\ = - 157 \: kjmol {}^{ - 1} [/tex]
What is the enthalpy of reaction?
O A. The amount of mass involved in a reaction
O B. The heat released or absorbed in a reaction
C. The amount of heat a substance can hold
D. A measure of the temperature of a system
Answer:
Enthalpy is the amount of heat released or absorb. The total enthalpy can be found by subtracting the products' enthalpy by the reactants' enthalpy
can someone explain the answer.
Answer:
A
Explanation:
Alkanes undergo substitution reaction with halogen molecules in the presence of light. This reaction occurs by free radical mechanism and the initiation step is the formation of the halogen radical.
The propagation steps involves the abstraction of a hydrogen from the alkane by the halogen radicals.
The termination steps involves the coupling of alky radicals.
Thus for the reaction of ethane and chlorine;
C2H6 + Cl2 -------> C2H5Cl + HCl
7. A sample of methane gas (CH.) with a mass of 58 g is kept in a 1500 mL container at a temperature of 100. °C. What is the pressure of the gas?
Answer:
c i took the text
Explanation:
If a shell can hold a maximum of 32 electrons, what is the value of n?
Answer:
The value of N would be 4.
Explanation:
The equation would be 2n^x = 32 and therefore, 4.
an unknown gas diffuses 1.25 times faster than CO2 gas. What is the molar mass of the unknown gas?
Answer:
28.16 g/mol
Explanation:
From Graham's law;
Let the rate of diffusion of gas X be 1.25
Let the rate of diffusion of CO2 be 1
Molecular mass of gas X= M
Molecular mass of CO2 = 44g/mol
1.25/1=√44/M
(1.25/1)^2 = 44/M
1.5625 = 44/M
M= 44/1.5625
M= 28.16 g/mol
copper +sulfur + oxygen =
State three pieces of evidence from the diagram which indicate that the plant is pollinated by wind. ( 3 marks)
Your image is saying "Can't load image on this device."
1) list at least four uses of metals from your day to day life.
Answer:
alloy,copper,gold, silver,cobalt
Explanation:
EJEMPLOS DE SOLUCIONES QUÍMICAS EN LA NATURALEZA
ahí esta la respuesta espero que te sirva
Which list BEST identifies how the arrows should be arranged around the paper leaf in the model to represent the movement of matter and flow of energy during photosynthesis? A. Point into Leaf: sugars, oxygen (02), Point away from leaf: carbon dioxide(CO2), water(H2O) B. Point into Leaf: sugars, sunlight, Point away from leaf: carbon dioxide(CO2), oxygen (02), water(H2O) C. Point into Leaf: water(H2O), sunlight, Point away from leaf: carbon dioxide(CO2), sugars, oxygen (02) D. Point into Leaf: water(H2O), carbon dioxide(CO2) sunlight, Point away from leaf: sugars, oxygen (02
Answer:
D. Point into Leaf: water(H₂O), carbon dioxide (CO₂) sunlight, Point away from leaf: Sugars, oxygen (O₂)
Explanation:
Photosynthesis is the process used in the production of chemical energy in the form of energy containing organic compounds and oxygen from atmospheric carbon dioxide and liquid water enabled with the energy captured from light (mainly Sunlight) by the chlorophyll in green plants and other organisms
The basic chemical reaction involved in a photosynthesis reaction is presented as follows;
[tex]{}[/tex] Sunlight
[tex]{}[/tex] ↓
[tex]{}[/tex] CO₂ + H₂O (l) → C₆H₁₂O₆ + O₂
Carbon dioxide [tex]{}[/tex] Water Glucose Oxygen
water is to ____as liquid is to soild
water is to gas as liquid is to solid
