Help on science question please! (Small drawing) will mark brainliest

Answer:

Eu não sei o que você está dizendo, mas boa sorte

Answer: Virtual

Explanation:  A virtual image is an image that can not be formed on a screen. This type of an image is formed when the rays of light appear to meet at a point after reflection or refraction. Virtual images are always erect or upright.

Answer:

1. sublimation

2.melting

3.melting  

4.sublimation

Explanation:

melting is a process when solid changes to liquid

Sublimation is the transition of a substance directly from the solid to the gas state, without passing through the liquid state.

Answer: c

Explanation: an xray wave does have a higher frequency than an infrared wave.

Answer:

Explanation:c

Answer:

Hey!

Your answer is element A

Explanation:

Using the graph, the element A's emission of radioactive particles ends approximately after 6 years...

A HALF-LIFE IS "HALF" OF THAT TIME PERIOD!

So if the radiation goes for 6 years the half-life is 6 divided by two which gives you 3 years!

The rest however have a longer half-life...

Because they all end at 14 yrs so their half-life in 7 years!

HOPE THIS HELPS!!

Answer:

1.84 atm

Explanation:

P2=V1P1/V2

Temp is irrelevant because it is constant, so all you have to do is rearrange the ideal gas law.

You can check this by knowing P and V at constant T have an inverse relationship and therefore makes this the correct answer.

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Answer:

[tex]\rm _{38}^{91}Sr \longrightarrow \, _{-1}^{0}e + \, _{39}^{91}Y[/tex]

Explanation:

The unbalanced nuclear equation is

[tex]\rm _{38}^{91}Sr \longrightarrow \, _{-1}^{0}e \, + \, ?[/tex]

Let's write the question mark as a nuclear symbol.

[tex]\rm _{38}^{91}Se} \longrightarrow \, _{-1}^{0}e \, + \, _{Z}^{A}X[/tex]

The main point to remember in balancing nuclear equations is that the sums of the superscripts and the subscripts must be the same on each side of the equation.  

Then

98 =  0 + A, so A =  98 -  0 = 98, and

38 = -1 + Z, so Z  = 38 + 1 = 39

Then, your nuclear equation becomes

[tex]\rm _{38}^{91}Sr \longrightarrow \, _{-1}^{0}e + \, _{39}^{91}X[/tex]

Element 39 is yttrium, so the balanced nuclear equation is

[tex]\rm _{38}^{91}Sr \longrightarrow \, _{-1}^{0}e + \, _{39}^{91}Y[/tex]

Answer:

butane

Explanation:

Answer:

Your answer is cells. Hope this helps!

Answer:

C

Explanation:

The answer is always C

Answer:C. Concave mirror

Explanation:

When the surface of a mirror curves inward, like the inside of a bowl, it is called c. Concave mirror.

Answer: A. the age of a layer of rock

Explanation:

Index fossils are of organisms that lived over a wide area. They lived for a fairly short period of time.

Index fossils are found throughout the world and come from organisms which existed during the limited periods of geologic time. Index fossils can be used to determine the age of a layer of rock. Thus, the correct option is A.

Index fossil is any kind of animal or plant that is preserved in the rock record of the Earth which is characteristic of a particular span of geologic time. A useful index fossil must be distinctive or is easily recognizable, abundant, and have a very wide geographic distribution and also a short range through time.

Index fossils are used to define the geological periods or the age of a layer of rock. These fossils can be defined as the commonly found, widely distributed fossils that are limited in time span. If a person finds an index fossil in a given layer, then he has bounds on the age of the layer.

Therefore, the correct option is A.

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The  oxidation state is zero for Fe (s)

Answer:

485 torr

Explanation:

Explanation:

We can solve this equation using the combined gas law:

P1V1/T1=P2V2/T2

Remember, always use the absolute (Kelvin) temperature when working with gas equations.

The temperature conversions are

T1=C+273=35o+273=308K

T2=57C+273=330K

Since we're trying to find the final pressure, let's rearrange this equation to solve for

P2:

P2=P1V1T2/T1V2

Our known values:

P1= 550 torr

V1=350mL

T1=308K

V2=425"mL

T2=330K

Let's plug these into the equation to find the final pressure:

The final pressure after it is subjected to these changes is thus 485torr

Answer:

b. The substance spilled on his hand is an acid. The base in the soap will neutralize the acid to make it stop burning.

Explanation:

In this case, the substance spilled on the hand is an acid, so it will require neutralization. In neutralization reactions, you have an acid and a base, which will be soap. This reaction is known as saponification.

Answer: conjugate base

Explanation:

According to the Bronsted-Lowry conjugate acid-base theory, an acid is defined as a substance which looses donates protons and thus forming conjugate base and a base is defined as a substance which accepts protons and thus forming conjugate acid.

A weak acid has a strong conjugate base whereas a strong acid has a weak conjugate base. Similarly a weak base has a strong conjugate acid whereas a strong base has a weak conjugate acid.

[tex]CH_3COOH+NH_3\rightarrow CH_3COO^-+NH_4^+[/tex]

Acetic acid [tex]CH_3COOH[/tex] is weak acid which has strong conjugate base [tex]CH_3COO^-[/tex]

Answer:

D. the physical and chemical properties of the products are different from the reactants

Explanation:

A student determines that she used 0.0665 mole of sodium hydroxide (NaOH) to completely titrate 25.00 mL of sulfuric acid solution. The molarity of the sulfuric acid is 1.31 M. Therefore, option C is correct.

Number of moles of solute per liter of solution is known as molarity.

The balanced chemical equation for the reaction between sodium hydroxide and sulfuric acid is:

2 NaOH + H₂SO₄ → Na₂SO₄ + 2 H₂O

According to the balanced equation, one mole of sulfuric acid reacts with two moles of sodium hydroxide. Therefore, the number of moles of sulfuric acid in the titrated solution can be calculated as:

moles of H₂SO₄ = (moles of NaOH) / 2

moles of H₂SO₄ = 0.0665 mol / 2

moles of H₂SO₄ = 0.03325 mol

The volume of the sulfuric acid solution used in the titration is 25.00 mL, which is equivalent to 0.02500 L. The molarity (M) of the sulfuric acid can be calculated as:

Molarity of H₂SO₄ = moles of H₂SO₄ / volume of H₂SO₄ solution in liters

= 0.03325 mole / 0.02500 L

= 1.31 M

Thus, option C is correct.

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Answer:

Approximately [tex]-74.8\; \rm kJ \cdot mol^{-1}[/tex].

Explanation:

Number the three reactions with known enthalpy changes:

[tex]\begin{aligned}& {\rm C\; (s) + O_2\; (g) \to CO_2\; (g)} & \quad \Delta H = -393.5\; \rm kJ\cdot mol^{-1}& \quad (1) \\ & {\rm H_2\; (2) + \frac{1}{2} O_2\; (g) \to H_2O\; (l)} & \quad \Delta H = -285.8\; \rm kJ\cdot mol^{-1} & \quad (2) \\ & {\rm CH_4\; (g) + 2\; O_2\; (g) \to CO_2\; (g) + 2\; H_2O\; (l)} & \quad \Delta H = -890.3\; \rm kJ\cdot mol^{-1} & \quad (3)\end{aligned}[/tex].

The goal is to find a way to combine these three reactions to obtain: [tex]\rm C\; (s) + 2\; H_2\; (g) \to CH_4\; (g)[/tex].

Assume that the three known reactions are combined in this way:

[tex]a \times (1) + b \times (2) + c \times (3)[/tex].

That corresponds to:

[tex]\begin{aligned} & a\; \mathrm{C\; (s)} + \left(a + \frac{1}{2}\, b + c\right) \; \mathrm{O_2\; (g)} + b\; \mathrm{H_2\; (g)} + c\; \mathrm{CH_4\; (g)} \\ & \to (a + c)\; \mathrm{CO_2\; (g)} + (b+ 2\,c )\; \mathrm{H_2O\; (l)}\end{aligned}[/tex].

Compare the coefficients of this reaction with that of the desired reaction:

[tex]\rm C\; (s) + 2\; H_2\; (g) \to CH_4\; (g)[/tex].

Note that some species (e.g., [tex]\rm CH_4\; (g)[/tex]) appeared on the wrong side of the equation. Their desired coefficient should be the opposite of their true coefficient. For example, the coefficient of [tex]\rm CH_4\; (g)[/tex] is supposed to be [tex]1[/tex]. However, because it appeared on the wrong side of the equation, its desired coefficient would be [tex]-1[/tex].

The coefficients of species that are not in the desired equation should be zero.

[tex]\begin{array}{|c|c|c|}\cline{1-3}\text{Species} & \text{Coefficient}& \text{Desired Coefficient} \\ \cline{1-3} \mathrm{C\; (s)}} & a & 1 \\ \cline{1-3} \mathrm{O_2\; (g)} & a + (1/2)\, b + c & 0 \\ \cline{1-3} \mathrm{H_2\; (g)} & b & 2 \\ \cline{1-3}\mathrm{CH_4\; (g)} & c & -1\\ \cline{1-3} \mathrm{CO_2\; (g)} & a + c & 0 \\ \cline{1-3} \mathrm{H_2O\; (l)} & b + 2\, c & 0\\ \cline{1-3}\end{array}[/tex].

Solve for [tex]a[/tex], [tex]b[/tex], and [tex]c[/tex]:

In other words, the desired equation is equal to [tex]1 \times (1) + 2 \times (2) - 1 \times (3)[/tex].

By Hess's Law, the enthalpy of the desired equation will be:

[tex]\begin{aligned}& 1\times \Delta H (1) + 2 \times \Delta H (2) - 1\times \Delta H(3) \\ &\approx -393.5 + 2 * (-285.8) - (-890.3) \\ &= -74.8\; \rm kJ \cdot mol^{-1} \end{aligned}[/tex].

Answer:

condensation: moisture builds up on window; dew forms on blades of grass

deposition: snow is made inside a cloud; frst froms on window?

Explanation:

Answer:

A

Explanation:

Neutralization reaction is

base + acid ---> salt + water.

Answer:

1. A. The plant leans toward window.

Explanation:

Plants need light to perform photosynthesis and live. Therefore, this means the plant will always lean toward light in order to survive.

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Answer

Last one I think

Explanation:

Answer:

el nino: the boy

la nina: the girl

Explanation:

Answer:

el nino is dinosour la nino is fishcat

Explanation:

Answer: The tides are another interaction in the sun-earth-moon system. The tides happen because the moon and sun pull on the oceans, causing them to rise and fall each day. The moon has a bigger effect than the sun because it is closer. The angle of the sun as the earth orbits over the course of a year causes the seasons.

Explanation:

Answer:

The abyssal plains

Explanation:

this is because it is so dark and devoid of resources that it is hard for most forms of life to survive

pls make me brainliest :) I'm trying to become an Ace

Answer:

abyssal

Explanation:

Answer:

A

Explanation:

Unlike the female reproductive system, the most parts of the male reproductive system are located outside the body. The mentioned part in the given diagram is urethra and it Mixes sperm and semen. The correct option is A.

The male reproductive system includes the testes, scrotum, spermatic ducts, male accessory glands and phallus. All these organs work together to produce sperms, the male gamete, male sex hormones and other components of semen.

The phallus and urethra are the parts of both the reproductive and urinary systems. Scrotum, seminal vesicles, vas deferens, testicles and prostate constitute all the remaining male reproductive system.

The urethra is a tube like structure which is the region included in the urinary tract that takes the urine from the bladder where the semen is ejaculated.

Thus the correct option is A.

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Answer:

c

Explanation:

the carbon cycle is the process in which carbon travels from the atmosphere into organisms and the earth and then back into the atmosphere

Answer:

[tex]\frac{1}{6}[/tex]

Explanation:

Molar ratio is defined as the ratio of number of moles of reactants or products in a balanced chemical equation.

In this balanced equation, the number of C6H6 molecules react to form 12 CO2 molecules.

Thus, the molar ratio between C6H6 to  carbon will be equal to 2 moles of  C6H6 divided by 12 moles of CO2

[tex]\frac{2}{12}\\\frac{1}{6}[/tex]

Answer:the objects will be about the same temperature as the room

Explanation: