These are the last two questions on the sheet I need help with haha, help only the ones you can! (most helpful answer will get brainliest)

Answer:

Excretion is the process of removing wastes from the body. Organs of the excretory system include the kidneys, large intestine, skin, and lungs.

The excretory system removes metabolic wastes from the body. The major organs of excretion are the kidneys, a pair of bean-shaped organs located below the liver. The kidneys filter blood and regulate water balance in the body

Answer:

2.47 L

Explanation:

The first thing we do is to write the balanced equation, which is.

CH4(g) + 2O2(g) --> CO2(g) + 2H2O(g)

Now, using ideal gas equation, we see that

PV = nRT

moles of methane

where P is the pressure, 1.65 atm

V is the volume, 2.8 L

R is the ideal gas constant, 0.0821

T is the temperature in Kelvin, 25 + 273 = 298 K

n = PV/RT

n of methane = 1.65 * 2.8 / 0.0821 * 298

n of methane = 4.62 / 24.47

n of methane = 0.189 mole

moles of O2:

PV = nRT

where P is the pressure 1.25 atm

V is the volume, 35 L

R is the ideal gas constant, 0.0821 L

T is the temperature, 31 + 273 = 304 K

n of O2 = 1.25 * 35 / 0.0821 * 304

n of O2 = 43.75 / 24.96

n of O2 = 1.75 mol

from the equation, the molar ratio between O2 and CH4 is 2:1, so therefore

no of moles of O2 = 2 * .0189 moles of methane = 0.378 mole

when 1 mole of CH4 --> 1 mole of CO2

1 mol of CO2 --> 22.4 L CO2

volume of CO2 at STP = [(0.189 moles of CH4 /1) * (1 mol of CO2)] / [(1 mole CH4) * (22.4L CO2)/(1 mol of CO2)] = 4.23 L

Next, we use the formula

P1V1 /T1 = P2V2/T2

where

P1 = 1 atm

V1 = 4.23 L

T1 = 273

P2 = 2.5 atm

T2 = 125 + 273 = 398 K, making V2 subject of formula, we have

V2 = P1V1T2 / T1P2

V2 = 1 atm * 4.23 L * 398 / 273 * 2.5 atm

V2 = 1683.54 / 682.5

V2 = 2.47 L

Answer:

I believe the answer is b

Answer:

it's already Balanced

MgO + Li2SO4 ---------✓ MgSO4 + Li2O

Answer:

Polar solvents because polar substances are likely to dissolve in polar solvents.

Explanation:

(pls mark me brainliest)

Answer:

a polar solvent

Answer:

3.44× 10²³ atoms

8.73× 10²⁵ molecules

37.64 × 10²³ molecules

0.014 × 10²³ molecules

Explanation:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 × 10²³ molecules of water

1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen

a) 0.572 moles of Al:

1 mole = 6.022 × 10²³ atoms

0.572 mol  ×  6.022 × 10²³ atoms / 1 mol

3.44× 10²³ atoms

b) 1.45× 10² moles of SO₂:

1 mole = 6.022 × 10²³ molecules

1.45 mol × 10² ×  6.022 × 10²³ molecules / 1 mol

8.73× 10²⁵ molecules

c) 6.25 moles of Ca(OH)₂

1 mole = 6.022 × 10²³ molecules

6.25 mol  ×  6.022 × 10²³ molecules / 1 mol

37.64 × 10²³ molecules

d) 0.0024 moles of CO₂

1 mole = 6.022 × 10²³ molecules

0.0024 mol  ×  6.022 × 10²³ molecules / 1 mol

0.014 × 10²³ molecules

Answer:

A substance consisting of 3.7 grams of beryllium fluoride would be equal to how many moles of beryllium  fluoride?

How many grams of sodium are equal to 1.5 moles of sodium?

Explanation:

The molar mass is related to number of moles and mass of an element or compound.

 Using the expression:

  Number of moles  = [tex]\frac{mass}{molar mass}[/tex]  

  For any problem, where the number of moles is known, we can find the mass.

A substance consisting of 3.7 grams of beryllium fluoride would be equal to how many moles of beryllium fluoride?

Here we know the mass, we simply use the molar mass to find the number of moles.

How many grams of sodium are equal to 1.5 moles of sodium?

Here number of moles is given, we use the molar mass to find the mass of the sodium given

Answer:

Induction

Explanation:

When a body is brought in contact with another, electrons are rearranged by contact.

When a body is rubbed against one another, charging by friction occurs.

The process whereby electrons are rearranged without direct contact with one another is called induction.

By induction electrons can get charged without them having to be in contact with one another.

Answer:

Carbon dioxide is a compound

Explanation:

It is formed by chemical combination of carbon and oxygen atoms

Answer:

there would be chemicals on the food.

Explanation: Hope this helps :)

Answer:

I think it's the electron dot structure for oxygen

Answer:

D.HI

Explanation:

because this is the most different

Answer:

10.24 ×10²³ molecules

Explanation:

Given data:

Mass of COCl₂ = 218.4 g

Number of molecules = ?

Solution:

Number of moles of COCl₂:

Number of moles = mass/molar mass

Number of moles = 218.4 g/ 129.84 g/mol

Number of moles = 1.7 mol

1 mole contain 6.022×10²³ molecules.

1.7 mol × 6.022×10²³ molecules / 1mol

10.24 ×10²³ molecules

Answer:

C

Explanation:

they can be put in other languages

they are literally the name of the chemical

they don't show quantity

The "major drawback" to using word equations is that they are not quantitative. Option C is correct.

Chemical reactions are written in word equations to give a clear and concise understanding of the reaction taking place. However, word equations are not quantitative. A equation is a way of representing a chemical reaction using words. It identifies the reactants and products and their physical states as well as the condition under which the reaction is taking place.

For example, the word equation for the reaction between hydrogen gas and oxygen gas to produce water is:

Hydrogen gas + oxygen gas → water

Quantitative equations use chemical formulas, numbers and symbols to represent the reactants and products in a chemical reaction. They provide a quantitative understanding of the reaction in terms of the number of atoms and molecules involved.

Know more about equations:

https://brainly.com/question/29657983

#SPJ6

Answer:

brain cell

Explanation:

hope this helps :)

Answer:

Lithium is an alkali metal. The symbol for lithium element is ‘Li’. It belongs to group 1 of periodic table. Its electronic configuration is 1s2 2s1. It has one valence electron. So it loses one electron to attain stable configuration. Hence the symbol for lithium ion is ‘Li+’.

Explanation:

ithium is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the lightest metal and the lightest solid element. Like all alkali metals, lithium is highly reactive and flammable, and must be stored in mineral oil. When cut, it exhibits a metallic luster, but moist air corrodes it quickly to a dull silvery gray, then black tarnish. It never occurs freely in nature, but only in compounds, such as pegmatitic minerals, which were once the main source of lithium. Due to its solubility as an ion, it is present in ocean water and is commonly obtained from brines. Lithium metal is isolated electrolytically from a mixture of lithium chloride and potassium chloride.

Answer:

C

Explanation:

C.OD diverse offspring with the same genes as the parent

Answer:

D

copper (II) sulfate pentahydrate

==>

[tex]CuSO _{4}.5H _{2}O[/tex]

Answer:

Neon

Explanation:

Carbon has an atomic mass of 12

Neon has an atomic mass of 20

Answer: electrons are found outside the nucleus.

Explanation:

Answer:

because its polluting the waters and they want to see if its harming the small sea life living in those locations

Explanation:

im 90% sure abt this srry if its wrong

a. solar energy

the earth is warmed by the sun, which is solar (or infrared).

Answer:

unevenly

Explanation:

Fresh water is distributed unevenly in both time and space.

a. 2 M

b. 1.5 M

Given

a 4 moles in 2 dm of solution?

b 0.3 moles in 200 cm3 of solution

Required

The concentration of a solution

Solution

Molarity shows the number of moles of solute in every 1 liter of solution or mmol in each ml of solution

Can be formulated :

[tex]\large \boxed {\bold {M ~ = ~ \dfrac {n} {V}}}[/tex]

a.

moles(n) = 4

volume(V)=2 L solution

M = 4 : 2 = 2

b.

moles(n)=0.3

volume(V)=200 cm3 = 0.2 L

M = 0.3 : 0.2 = 1.5

Answer:

Average atomic mass of X= 64.25 amu

Explanation:

Abundance of X-64 = 80%

Abundance of X-65 = 15%

Abundance of X-66 = 5%

Average atomic mass = ?

Solution:  

Average atomic mass of X = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass)  + (abundance of 3rd isotope × its atomic mass)  / 100

Average atomic mass of X= (80×64)+(15×65) +(5×66) /100

Average atomic mass of X =  5120 + 975 + 330 / 100

Average atomic mass of X  = 6425/ 100

Average atomic mass of X= 64.25 amu.