lab safety test Safety goggles and an apron must be worn when handling chemicals labeled corrosive because they:________.

Answers

Answer 1

Answer:

The terms of biosafety in a laboratory require that the person must not have the eyes and skin exposed.

Explanation:

A corrosive substance is a substance that can damage a surface when they come into contact.

These substances represent a danger in people since they can burn the eyes, the skin, and the inside of the body since the inhalation of gases can burn the respiratory tract.

These chemical burns can be avoided by properly following the biosafety protocol that a laboratory requires the use of masks, goggles, gloves, and an apron or lab coat.


Related Questions

Q3. Three ants 1, 2 and 3 are pulling a grain with forces of magnitude 10 N, 4 N and FN as shown in the figure. Find the force F if the grain remains in equilibrium under the action of the above forces.​

Answers

Answer:

F = 7.21 N

Explanation:

There are two methods to find the magnitude of F.

The first method is the analytical one and the second one is the geometrical one.

The easiest is the geometrical one.

We will start with it

■■■■■■■■■■■■■■■■■■■■■■■■■■

● Method 1:

The geometrical method

The grain remains in equilibrum under the action of 3 forces.

The 3 forces must give if joined together a close path.

There are 3 forces so the resulting shape is a triangle. (Picture 1)

● Al Kashi theorem:

We will use Al Kashi theorem (law of cosine) to find the magnitude of F.

● F^2 = b^2 + c^2 + 2bc×cosA

● F^2 = 10^2 + 4^2 + 2×10×4 × cos(37°)

● F^2 = 52.1

● F = 7.21 N

■■■■■■■■■■■■■■■■■■■■■■■■■■

● method 2 (analytical one)

This method is based on projecting each vector on the x and y axis.

Since the grain remains in equilibrum the relation between the vectors is:

● Vector F + Vector 1 + Vector 2 = Null vector

Vector one is the one with 4 N magnitude and 2 is the 10 one.

Project each vector following the x-axis and the y-axis and add them together.

(Picture 2)

● x-axis

F1 is the 4 N force and F2 is the 10 N one

● Fx + F1x + F2x = 0

● Fx -4 + 10 × cos(37°) = 0

F1x is negative since it goes toward the negatives numbers. It is parallel to the x-axis that's why we have put directly the magnitude

Fx2 is not parallel to the x-axis that's why we have expressed it using the cosine relation. (Picture 3)

● Fx -4 + 10 × cos(37°) = 0

● Fx = 4 -10 × cos(37°)

● Fx = -4 after rounding to the nearest unit

● y-axis

● Fy + F1y + F2y = 0

● Fy + 0 + sin(37°) × 10 = 0

F1y equals 0 since when projecting the vector's head and tail, both were in the same point. In other words the direction of the vector was perpendicular to the y-axis.

F2y is'nt parallel to the y-axis. That's why we have expressed it using the sine.

● Fy + sin(37°)×10 =0

● Fy = -10×sin(37°)

● Fy = -6 after rounding it to the nearers unit

Notice that F, Fx and Fy are creating a right triangle.(picture 4)

● The Pythagorian theorem

● F^2 = Fx^2 + Fy^2

● F^2 = (-4)^2 + (-6)^2

● F^2 = 16+36

● F^2 = 52

● F^2 = 7.21 N

That's the same result we got using the first method.

Answer:

F = 7.21 N

Explanation:

horizontal sum of forces = ∑h = 10 cos(37) - 4 = 3.98 N

vertical sum of forces = ∑v = 10 cos(90-37) = 6.02 N

therefore, the resultant F² = ∑h² + ∑v²

F = sqrt (3.98² + 6.02²)

F = 7.21 N

Question 2 (1 point)
In a competition, an athlete threw a flying disk 178.7 meters through the air. While
in flight, the disk traveled at an average speed of 13.6 m/s. How long did the disk
remain in the air?
Your Answer:
Answer
units

Answers

according to the facts it should be a numerous amount of wrong answers so ignore dis

600 pages of a book have a total mass of 0.6kg; calculate the mass of each sheet of paper in the book in (i) Kilograms (ii) Milligram

Answers

Answer:

[tex]1g = 1000mg \\ \: \: \: \: \: \: \: \: = 0.001kg[/tex]

Explanation is attached to the picture

hope this helps

brainliest plz

a ball is thrown down at 25 m/s from a 500m tall building. how fast is it traveling when it hits the ground?

Answers

Answer:

The speed of the ball when it hits the ground is 102.1 m/s

Explanation:

Given;

initial velocity of ball, u = 25 m/s

distance traveled by the ball = height of the building = h = 500 m

when the ball hits the ground, the final velocity, v = ?

The final velocity of the ball is given by;

v² = u² + 2gh

where;

g is acceleration due to gravity = 9.8 m/s²

v² = (25)² + 2(9.8)(500)

v² = 10425

v = √10425

v = 102.1 m/s

Therefore, the speed of the ball when it hits the ground is 102.1 m/s

a ballon filled with nitrogen gas has a small leak. Another ballon filled with hydrogen gas has an identical leak. How much faster will the hydrogen balloon deflate

Answers

Answer:

4 times that of nitrogen gas, N2.

Explanation:

Let R1 be the rate of diffusion of nitrogen gas, N2.

Let R2 be the rate of diffusion of Hydrogen gas, H2.

Let M1 be the molar mass N2

Let M2 be the molar mass of H2.

Next, we shall determine the molar mass of N2 and H2.

This is illustrated below below:

Molar mass of N2 (M1) = 2 x 14 = 28 g/mol

Molar mass of H2 (M2) = 2 x 1 = 2 g/mol

Finally, we shall determine the rate of diffusion of Hydrogen gas, H2 as follow:

R1/R2 = √(M2/M1)

M1 = 28

M2 = 2

R1/R2 = √(M2/M1)

R1/R2 = √(2/28)

R1/R2 = √(1/14)

R1/R2 = 0.27

Cross multiply

R1 = R2 × 0.27

Divide both side by 0.27

R2 = R1/0.27

R2 = R1 × 1/0.27

R2 = R1 × 4

R2 = 4R1

Therefore, the rate of diffusion of H2 (R2) is 4 times that of N2 (R1)

who was albert einstien describe his contributions???

Answers

Answer:

Albert Einstein was from Germany he was born theoritical physicist, from childhood only he loved mechanical toys, he was highly gifted in Mathematics, He was a world citizen and a scientific genius too. His contribution were:

1) he developed the theory of relativity

2) he also discovered the process of nuclear fission

3)he developed the quantum theory of specific heat

4)theory of stimulated emission, on which laser device technology is based

5) law of photoelectric effect

hope it helped you :)

How does a arrow represent displacement

Answers

Answer:

An arrow represents displacement. Because it's a vector quantity.

Vector quantity= Direction+Magnitude

When an arrow is put above a unit like

accelerationdisplacement

it means that it's a vector quantity.

Hope this helps ;) ❤❤❤

Suppose all of the apples have a mass of 0.10 kg. If apple (A) is sitting on the ground, what is its potential energy?

Answers

Answer:

The answer is C 0.0

Explanation:

Because its sitting still on the ground.

Answer:

0.0j

Explanation:

A submarine completed a 450 km training with an average speed of 50 km/h. For the first 180 km, it travelled at an average speed of 60 km/h. What was the average speed for the remaining distance? Km/h

Answers

Answer:

45km/hr

Explanation:

Total distance=450km

Total speed=50km/hr

Total time= distance/speed

=450/50

=9hrs

distance a=180km

speed a=60km/hr

Time a=180/60

=3hrs

Distance b=450-180=270km

Speed b=?

Time b=270/speed b

Total time=time a + time b

9=3+(270/speed b)

270/speed b =9-3

270/speed b =6

6*speed b =270

Speed b=270/6

Speed b=45km/hr

Answer:

45km/hr

Explanation:

Total distance=450km

Total speed=50km/hr

Total time= distance/speed

=450/50

=9hrs

distance a=180km

speed a=60km/hr

Time a=180/60

=3hrs

Distance b=450-180=270km

Speed b=?

Time b=270/speed b

Total time=time a + time b

9=3+(270/speed b)

270/speed b =9-3

270/speed b =6

6*speed b =270

Speed b=270/6

Speed b=45km/hr

When two bodies of different temperatures are placed together and left for sometime, Both of them attain the same temperature.
(Heat flows from a body of Higher temperature to a body of lower temperature)
Now after they attain the same temperature will there be
No transfer of heat between them
Or
Will there be an equal amount of heat lost and gained by both the bodies?​

My answer would be an equal amount of heat is lost and gained by both the bodies
You can't exactly say that there is no heat transfer just because equal amount is lost and gained by the bodies right?
My text book says that there is NO transfer of heat once both the bodies attain same temperature

Answers

hi olivia hope this helps you

What is the magnitude of displacement if a person goes 290 m east followed by 150 m west?

Answers

Answer:140 m

Explanation:

Displacement = 290-150= 140 m

A pair of narrow, parallel slits separated by 0.275 mm is illuminated by the green component from a mercury vapor lamp (λ = 546.1 nm). The interference pattern is observed on a screen 1.25 m from the plane of the parallel slit. Calculate the distance from the central maximum to the first bright region on either side of the central maximum.

Answers

Answer:

2.481 mm

Explanation:

Given that

Distance between the slits, d = 0.275 mm = 2.75*10^-4 m

Wavelength of the lamp, λ = 546.1 nm

Distance between slit and the screen, L = 1.25 m

To solve this question, we would be applying the formula for Young's double slit fringes, from the path difference equal to a whole number of wavelengths.

mλ = dy/L

The question states that we should find the distance from the centre to the 1st order bright fringe, thus, m = 1

Now, we apply all these values into the question

1 * 546.1*10^-9 = (2.75*10^-4 * y) / 1.25

1.25 * 1 * 546.1*10^-9 = 2.75*10^-4 * y

6.825*10^-7 = 2.75*10^-4 * y

y = 6.825*10^-7 / 2.75*10^-4

y = 0.002481 m or 2.481 mm

andy runs 40 meters east in 5 seconds and then 100 meters west in 15 seconds his average velocity is?

Answers

Answer:

[tex]\Large \boxed{3}[/tex]

Explanation:

Info given;

∵ 40 meters east in 5 seconds

∵ 100 meters west in 15 seconds

=> [tex](100 -40)[/tex]

=> Divided by;

=> [tex](5 + 15)[/tex]

=> [tex]3 m/s[/tex]

Answer; 3 m/s

(Average velocity is; 3 m/s )

Please help with theses 2 questions.

1. What is the name of 2F?

2.Using the diagram what is the name of the distance between O and 2F?

Answers

[tex] \huge{ \underline{ \underline{ \purple{ \bf{Answer:}}}}}[/tex]

1) Well, we know that lens is made by using 2 concave or convex mirror or sometimes we also use one plane mirror. The spherical mirrors are part of the glass sphere, and hence they have a centre and corresponding radius.

2F is double of focal length when light passes from one surface to another of the lens, so it can be said as the centre of curvature of the one of those spherical lens.

2) Distance between the optical centre and the centre of curvature is a lens can be termed as the radius of curvature of the lens. Well, we don't generally use these in case of lens. But still, the distance between O and 2F is double of the focal length or radius of curvature.

━━━━━━━━━━━━━━━━━━━━

Ariver is flowing at 3.6 m/s. A boy in a tube is floating the river downstream. If the boy can use
his arms to paddle at 1.7 m/s with the current, how fast will it appear he is moving to anyone on
the riverbank?

Answers

Answer:

The total speed is 5.3 m/s

Explanation:

The speed of river = 3.6 m/s

The speed of the tube that a boy use for downstream = 1.7 m/s

Now we have to find the total speed of the boy in the case of downstream. However, in this case, the total speed can be determined by adding both the given speeds.

The total speed = Speed of rive + speed of the tube

Total speed = 3.6 + 1.7

Total speed = 5.3 m/s

A charge of 19 nC is uniformly distributed along a straight rod of length 15 m that is bent into a circular arc with a radius of 5.7 m. What is the magnitude of the electric field at the center of curvature of the arc?

Answers

Answer:

The magnitude of the electric field at the center of curvature of the arc is 3.87 N/C

Explanation:

Please see the attachments below

From a hot air balloon that is at rest at a certain height, a projectile is launched horizontally at 30m / s, how fast will it have after 4s?

A. 50m / s
B. 60m / s
C. 70m / s
D. 80m / s

Answers

Answer:

A. 50 m/s

Explanation:

Given in the y direction:

v₀ = 0 m/s

a = 10 m/s²

t = 4 s

Find: v

v = at + v₀

v = (10 m/s²) (4 s) + 0 m/s

v = 40 m/s

In the x direction, the velocity is constant at 30 m/s.

The overall speed is:

v² = (30 m/s)² + (40 m/s)²

v = 50 m/s

The answer:

A) 50 m/s


Contrast the sizes between that of a red blood cell against a single motor neuron.

Answers

Answer:

Explanation:The average human adult has more than 5 liters (6 quarts) of blood in his or her body. Blood carries oxygen and nutrients to living cells and takes away their waste products. It also delivers immune cells to fight infections and contains platelets that can form a plug in a damaged blood vessel to prevent blood loss


What does this student most likely need to do in order to be better prepared to stay safe in a lab?
take off the goggles
change into lighter shoes
wear different clothing
tie back her hair

Answers

she needs to tie back her hair

Perform the calculation and report your answer using sig figs. 126.3851 + 7.2 + 73.607 + 15.98

Answers

Answer:

223.2

Explanation:

126.3851 + 7.2 + 73.607 + 15.98 = 223.1721

When adding/subtracting, round to the fewest decimal places.  7.2 has 1 number after the decimal point, so we'll round our answer to 223.2.

A ball rolling on the floor is an example of motion. a random b) translatory c) multiple d) rotatory​

Answers

Answer:

Actually it is linear motion but here option is not given so the best option is translators motion.

Explanation:

Hope it will help you :)

Answer:

d rotatory motion

Explanation:

A running back with a mass of 70 kg travels down the field with a velocity of 5.0 ms . Calculate the kinetic energy of the football player

Answers

Explanation:

KE = ½ mv²

KE = ½ (70 kg) (5.0 m/s)²

KE = 875 J

How does work affect energy between objects so it can cause a change in the form of energy? Work transfers energy. Work changes energy. Work increases energy. Work decreases energy.

Answers

'Doing work' is a way of transferring energy from one object to another, energy is transferred when a force moves through a distance.

If i explain with formula

Work done (J) = Energy transferred (J)

So more energy, more work done bc u transferred more energy to move the object and doing the work. and if you only use a little of energy, the work done also only a little.

Work affect energy between objects so it can cause a change in the form of energy by transferring energy.

According to work energy theorem, the work done on an object is directly proportional to the change in the average kinetic energy of the body.

For example, a catapult used to project a stone, does a work by converting or transferring its stored elastic potential energy into kinetic energy of the flying stone.

Thus, we can conclude that work affect energy between objects so it can cause a change in the form of energy by transferring energy.

Learn more here: https://brainly.com/question/10063455

How long will it take a charter bus full of people traveling 216 km/hr from Georgia to go 36 km to Florida's
Disney World theme park?

Answers

Answer:

t = 10.02 minutes

Explanation:

It is given that,

Speed of bus, v = 216 km/h

Distance to be traveled by the bus, d = 36 km

We need to find the time taken by the bus to cover the distance. Let the time is t.

Speed = distance/time

[tex]t=\dfrac{d}{v}\\\\t=\dfrac{36\ km}{216\ km/h}\\\\t=0.167\ h[/tex]

or

t = 10.02 minutes

So, 10.02 minutes is taken by the bus.

A tortoise travels 15 meters (m) west, then another 13 centimeters (cm) west. How many meters total has she walked?

Answers

Answer:

15.13m

Explanation:

change 15m to cm

1m=100cm

15m times 100=1500cm

add 1500+13 = 1513cm

in metres it will be 15.13m

Multiple of a unit of measure are found by multiplying the unit by an unteger larger than one

The total distance the tortoise walked in meters is 15.13 m

Reason:

Known parameter are;

The distance west the tortoise travels = 15 meters

The further distance west the tortoise walks = 13 cm = 0.13 m

Required:

The total (distance) in meters she has walked

Solution:

The total distance the tortoise walked in meters = 15 m + 0.13 m = 15.13 m

Learn more about multiples of units of measurement here:

https://brainly.com/question/1643372

A 12cm candle is placed 6cm from a converging lens with a focal length of 15cm. What is the height of the image of the candle? Show all calculations and use SALT to describe the image.

Answers

Answer:

The height of the image of the candle is 20 cm.

Explanation:

Given that,

Size of the candle, h = 12 cm

Object distance from the candle, u = -6 cm

Focal length of converging lens, f = 15 cm

To find,

The height of the image of the candle.

Solution,

Firstly, we will find the image distance of the candle. Let it is equal to v. Using lens formula to find the image distance.

[tex]\dfrac{1}{f}=\dfrac{1}{v}-\dfrac{1}{u}[/tex]

v is image distance

[tex]\dfrac{1}{f}=\dfrac{1}{v}-\dfrac{1}{u}\\\\\dfrac{1}{v}=\dfrac{1}{f}+\dfrac{1}{u}\\\\\dfrac{1}{v}=\dfrac{1}{15}+\dfrac{1}{(-6)}\\\\v=-10\ cm[/tex]

If h' is the height of the image. Magnification is given by :

[tex]m=\dfrac{h'}{h}=\dfrac{v}{u}[/tex]

[tex]h'=\dfrac{vh}{u}\\\\h'=\dfrac{-10\times 12}{-6}\\\\h'=20\ cm[/tex]

So, the height of the image of the candle is 20 cm.

Where on the periodic table would this element most likely be found? Group 1 Group 2 Group 12 Group 13

Answers

Answer:

The right approach will be Option C "Group 12".

Explanation:

A table that further arranges the chemical components in addition to expanding the electron configuration. Elements possessing identical characteristics are positioned in almost the same section (column or group), although elements in almost the same row become positioned with a similar amount of electron spheres.Group 12 components therefore partially replaced (n − 1)d subshells, and therefore aren't metals, technically accurate. However, although much their chemistry seems to be comparable to something like the components throughout the d block which includes establishing themselves.

Some other options in question are not relevant to something like the given scenario. Because then the option here is just the right one.

Answer:

option C group 12

Explanation:

i did the test

Nail tips exert tremendous pressures when they are hit by hammers because they exert a large force over a small area. What force (in N) must be exerted on a nail with a circular tip of 1.45 mm diameter to create a pressure of 2.33 ✕ 109 N/m2? (This high pressure is possible because the hammer striking the nail is brought to rest in such a short distance.)

Answers

Answer:

The  force is  [tex]F = 3587.2 \ N[/tex]

Explanation:

From the question we are told that

   The  diameter is  [tex]d = 1.4 \ mm = 0.0014 \ m[/tex]

    The pressure is  [tex]P = 2.33*10^{9} \ N/m^2[/tex]

Generally the radius is mathematically represented as

        [tex]r = \frac{0.0014}{2}[/tex]

        [tex]r = 0.0007 \ m[/tex]

 The  cross-sectional area of the nail is mathematically represented as

       [tex]A = \pi r^2[/tex]

=>     [tex]A = 3.142 * 0.0007 ^2[/tex]

=>    [tex]A = 1.54 *10^{-6}[/tex]

Generally the pressure is mathematically represented as

        [tex]P = \frac{F}{A}[/tex]

=>      [tex]F = P * A[/tex]

=>       [tex]F = 1.54*10^{-6} * 2.33*10^{9}[/tex]

=>      [tex]F = 3587.2 \ N[/tex]

A cross country skier moves 28 meters westward then 62 meters eastward and finally 54 meters westward

Answers

Answer:

The answer is below

Explanation:

A cross-country skier moves 28 meters westward, then 62 meters eastward, and finally 54 meters westward.

For this motion, what is the distance moved?

What is the magnitude and direction of the displacement?

Answer:

a) The distance moved is the summation of all the distance, therefore:

Distance = Distance first moved westward + Distance moved eastward + Final distance moved westward = 28 m + 62 m + 54 m = 144 m

Distance = 144 m

b) Displacement is a vector quantity (has magnitude and direction). The displacement is the shortest distance from the starting to final point.

Total distance westward = 28 m + 54 m = 82 m

Total distance eastward = 62 m

Displacement =  Total distance westward  - Total distance eastward = 82 m - 62 m = 20 m

Displacement = 20 m westward

The displacement has a magnitude of 20 m and the direction is westward

The work function for cesium is 1.96 eV. (a) Find the cutoff wavelength for the metal, (b) what is the maximum kinetic energy for the emitted electrons when 425 nm light is incident on the metal

Answers

Answer:

Explanation:

λ = hc/¢

Where

h = the Plank constant 6.63 x 10-34 Is

C = 3.0×10^8

¢= 1.96eV

= (6.63×10^-34Js)×(3×10^8)÷( 1.96eV) × 1eV/1.6×10^-19J

= (1.989×10^-25)÷( 1.96eV)×1eV/1.6×10^-19J

= 6.342×10^-7m

B) maximum kinetic energy

= K=hf−ϕ ........1

ϕ = hc

Where

​ h = constant 6.63 x 10^-34Js

ϕ= 1.96eV

Recall

λ =425×10^-9m

f = frequency in Hz

f = c / λ

C = 3.0×10^8

f = 3.0×10^8 / 425×10^-9m

f = 0.000705Hz

From equation 1

K = (6.63 x 10^-34Js×0.000705Hz )- 6.63 x 10^-34Js×3.0×10^8

= 4.68×10^-37 - 1.989×10^-25

= - 1.98×10^-25J

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