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3 years ago

Can someone help me pls will mark Brainly and 10+ points

Chemistry

1 answer:

bixtya [17]3 years ago

6 0

Answer:

Hope this helps :)

Explanation:

1. A physical property is a characteristic of matter that is not associated with a change in its chemical composition.

2. Matter is everything around you. Atoms and compounds are all made of very small parts of matter.

3. Solid, liquid and, gas

4. False

5. Our weight on moon is less than it would be on Earth due to a difference of the strength of gravity on the moon.

6. Physical changes only change the appearance of a substance, not its chemical composition. Chemical changes cause a substance to change into an entirely substance with a new chemical formula. Chemical changes are also known as chemical reactions.

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What are two lipids that store energy

timurjin [86]

Fats and oils are two lipids that store energy

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3 years ago

How does the mass of a bowling ball that has been rolled down the lane affect the kinetic energy?

Simora [160]

Answer is: B) The kinetic energy is increasing proportional to the mass of the bowling ball.

Kinetic energy has to do with the speed of an object and how much mass it has; basically how the object is moving.

Ek = 1/2 · m(bowling ball) · v²(bowling ball).

m is mass; v is speed of bowling ball.

The standard unit of kinetic energy is the joule.

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3 years ago

H2SO4 is a strong acid because the first proton ionizes 100%. The Ka of the second proton is 1.1x10-2. What would be the pH of a

forsale [732]

Question options:

a) 2.05

b) 0.963

c) 0.955

d) 1.00

Answer:

b) 0.963

Explanation:

H2SO4→ HSO4- + H3O+

HSO4- + H2O ⇌ SO42- + H3O+

Construct ICE table:

HSO4- (aq) + H2O ⇌ SO42- (aq) + H3O+ (aq)

I 0.1 solid & 0 0.1

C -x liquid + x + x

E 0.1 - x are ignored x 0.1 + x

Calculate x

Ka = products/reactants

= $\frac{[SO42-] [H3O+]}{[HSO4-]}$

0.011 = $\frac{x (0.1 + x)}{0.1 - x}$

0.011 x (0.1 -x) = o.1x + x^2

0.0011 - 0.011 x - o.1x - x^2 = 0

0.0011 - 0.011 x - x^2 = 0

Use formula to solve for quadratic equation

x = ${ -b +,-\sqrt{b^2 - 4ac$ / 2a

a = -1, b = -0.111, c = 0.001

Solve for x

x = $\sqrt[-(-o.111)]{(-0.111)^2 - 4(-1) (0.0011) }$ / 2(-1)

x = 0.111 +,- $\sqrt{0.012321 + 0.0044}$ / -2

x = 0.111 +,- $\sqrt{0.016721}$ / -2

x = $\frac{0.111 +, - 0.1293}{-2}$

x = $\frac{0.111 + 0.1293}{-2}$ , x = $\frac{0.111 - 0.1293}{-2}$

x = $\frac{0.2403}{-2}$ , x = $\frac{0.0183}{-2}$

x = - 0.12015 , x = 0.00915

x cannot be negative, so

x = 0.00915 M

Calculate [H3O+]

[H3O+] = 0.1 M + x

[H3O+] = 0.1 M + 0.00915 M

[H3O+] = 0.10915 M

Clculate pH

pH = - log [ H3O+]

pH = - log [ 0.10915]

pH = 0.963

8 0

3 years ago

What helps skin repair itself after it is cut?

vesna_86 [32]

A.

When you cut your skin the cells at the edge of the injury are stimulated to divide rapidly.

I hope this helps

7 0

3 years ago

Read 2 more answers

What is the frequency of radiation whose wavelength is 2.51 x 10 -7m?

hodyreva [135]

The frequency of radiation : 1.2 x 10¹⁵ Hz

<h3>Further explanation </h3>

Radiation energy is absorbed by photons

The energy in one photon can be formulated as

$\large{\boxed{\bold{E\:=\:h\:.\:f}}}$

Where

h = Planck's constant (6,626.10⁻³⁴ Js)

f = Frequency of electromagnetic waves

c = speed of light

= 3.10⁸ m/s

λ = wavelength

Wavelength-λ is 2.51 x 10⁻⁷m

The frequency :

$\tt f=\dfrac{3.10^8}{2.51\times 10^{-7}}=1.2\times 10^{15}$

8 0

3 years ago