Structural formulas show the arrangement of blank in molecules.

What effect does removing predators have on prey?

Lana71 [14]

What effect does removing predators have on prey?

:It means that as they are removed the predators go hungry and they could become extinct.

Hope I helped!

3 0

3 years ago

Read 2 more answers

Please help me with this questions, sorry:(

natulia [17]

Answer:

yes

Explanation:

the water may freeze at low winter temperatures but it will still be there

8 0

3 years ago

Methane is the main component of natural gas. Using the given reaction enthalpy, calculate the heat energy produced by the combu

SVETLANKA909090 [29]

Answer: The heat energy produced is 53831.25KJ

Explanation:

METHANE is the main component of natural gas. It can undergo combustion reaction in air with a bright blue flame to produce carbondioxide and water. The heat of reaction (enthalpy) is negative because heat is absorbed during the chemical reaction. To calculate the heat energy produced by the combustion of one kilogram (1 kg) of methane the following steps are taken:

Molecular mass of methane =16 gm/mol.

So moles of 1 kg methane =

Given mass of methane ÷ molecular weight of methane

But the given mass = 1kg = 1000g

Therefore,

moles of 1000g methane = 1000÷16

= 62.5 moles

Hence, energy evolved = (moles of methane) × (heat of combustion)

Therefore,

heat energy produced= 62.5 × (-861.3kj)

= -53831.25kj

7 0

3 years ago

what is the trend for the size as you go from Be to Mg to Ca? does the atomic size increase, decrease, or remain the same? how w

lys-0071 [83]

Answer:

the size of Ca is the greatest ,then Mg is the greater on size than Be

Explanation:

if you make the electron configuration for each of the elements, what is the main difference u gonna see ?

Be 4 1s2/2s2

Mg 12 1s2 /2s2 2p6/3s2

Ca 20 1s2 /2s2 2p6/3s2 3p6 3d/4s2

see that all the elements are in the same group but are in different period

u gonna see the last electron valance shell in Ca are too far from its nucleus but in Be the last electrons are too close and more attracted to the atom's nucleus , so the size of Ca is the biggest then Mg then Be

4 0

4 years ago

Hydrazine (N2H4) is used as rocket fuel. It reacts with oxygen to form nitrogen and water.

Marina86 [1]

Answer:

See explanation below for answers

Explanation:

This is a stochiometry reaction. LEt's write the overall reaction again:

N₂H₄ + O₂ ---------> N₂ + 2H₂O

This reaction is taking place at Standard temperature and pressure conditions (STP) which are P = 1 atm and T = 273 K. To know the volume of N₂ formed, we need to know first how many moles are formed, and this can be calculated with the reagents and the limiting reagent. Let's calculate the moles first of the reagents:

MM N₂H₄ = 32 g/mol; MM O₂ = 32 g/mol

mol N₂H₄ = 2000 / 32 = 62.5 moles

mol O₂ ? 2100 / 32 = 65.63 moles

Now that we have the moles, we need to apply the stochiometry and calculate the limiting reagent. According to the overall reaction we have a mole ratio of 1:1 between N₂H₄ and O₂, therefore:

1 mole N₂H₄ ---------> 1 mole O₂

62.5 moles ----------> X

X = 62.5 moles of O₂

But we have 65.63 moles, therefore, the limiting reactant is the N₂H₄.

We also have a 1:1 mole ratio with the N₂, so:

moles N₂H₄ = moles N₂ = 62.5 moles

Now that we have the moles, we can calculate the volume with the ideal gas equation:

PV = nRT

V = nRT / P

R: gas constant (0.082 L atm / K mol)

Replacing we have:

v = 62.5 * 0.082 * 273 / 1

V = 1399.13 L of N₂

Now, how many grams of the excess remains?, we know how many moles are reacting so, let's see how much is left:

moles remaining = 65.63 - 62.5 = 3.12 moles

then the mass of oxygen:

m = 3.12 * 32 = 100.16 g of O₂

7 0

3 years ago

Read 2 more answers