All categories

3 years ago

11th grade chemistry study guide need help

Chemistry

1 answer:

Nataly [62]3 years ago

7 0

Answer:

45) the answer is C.

46) The calculation of quantities in chemical reaction is called Stoichiometry .

47) The phase changed from solid to gas so I think the answer is A.

48) The phase changed from solid to gas as well so I think that the answer is A again.

49) Applying the formula n = m/M, we have n = 1.5 moles, therefore the answer is D.

50) C2H4 + 3O2 -> 2H2O + 2CO2

The answer is C.

51) The answer is C.

52) 2NaHCO3 + CaCl2 -> CaCO3 + H2O + 2NaCl + CO2

Hopefully I got all of them correct.

You might be interested in

The ostwald process is used commercially to produce nitric acid, which is, in turn, used in many modern chemical processes. in t

Debora [2.8K]

The complete balanced chemical equation is:
4 NH3 (g) + 5 O2 (g) → 4 NO (g) + 6 H2O (g)

In statement form: 4mol NH3 reacts with 5 mol O2 to produce 6 mol H2O

First let us find for the limiting reactant:
>molar mass NH3 = 17 g/mol
moles NH3 = 54/17 = 3.18 mol NH3
This will react with 3.18*5/4 = 3.97 mol O2

>molar mass O2 = 32g/mol
moles O2 = 54/32 = 1.69 mol O2
We have insufficient O2 therefore this is the limiting reactant

From the balanced equation:
For every 5.0 mol O2, we get 6.0 mol H2O, therefore

moles H2O formed = 1.69 mol O2 * 6/5 = 2.025 mol
Molar mass H2O = 18g/mol
mass H2O formed = 2.025*18 = 36.45 grams H2O produced

8 0

3 years ago

Read 2 more answers

A battery has an electrical ______________ energy

aleksley [76]

Answer:

Electrical Energy

Explanation:

There are a variety of chemical and mechanical devices that are called batteries, although they operate on different physical principles. A battery for the purposes of this explanation will be a device that can store energy in a chemical form and convert that stored chemical energy into electrical energy when needed.

5 0

2 years ago

Select the correct value for the indicated bond angle in each of the following compounds: O-S-O angle of SO2 F-B-F angle of BF3

Stels [109]

Answer:

(A) O-S-O bond angle of SO₂ molecule = 119°

(B) F-B-F bond angle of BF₃ molecule = 120°

(D) O-C-O bond angle of CO₂ molecule = 180°

(E) F-P-F bond angle of PF₃ molecule = 96.3°

(F) H-C-H bond angle of CH₄ molecule = 109.5°

Explanation:

Bond angle refers to the angle between two adjacent chemical bonds in a molecule. The bond angle is different for different molecular geometry.

The Valence shell electron pair repulsion theory predicts the molecular geometry and shape of the given molecule by the number of lone pairs on central atom and number of atoms bonded to central atom.

(A) SO₂ molecule

The number of atoms bonded to S = 2

Number of lone pairs on S = 1

Therefore, the shape of SO₂ molecule is bent and the O-S-O bond angle is 119°.

(B) BF₃ molecule

The number of atoms bonded to B = 3

Number of lone pairs on B = 0

Therefore, the shape of BF₃ molecule is trigonal planar and the F-B-F bond angle is 120°.

(C) SCl₂ molecule

The number of atoms bonded to S = 2

Number of lone pairs on S = 2

Therefore, the shape of SCl₂ molecule is bent and the Cl-S-Cl bond angle is 103°.

(D) CO₂ molecule

The number of atoms bonded to C = 2

Number of lone pairs on C = 0

Therefore, the shape of CO₂ molecule is linear and the O-C-O bond angle is 180°.

(E) PF₃ molecule

The number of atoms bonded to P = 3

Number of lone pairs on P = 1

Therefore, the shape of PF₃ molecule is trigonal pyramidal and the F-P-F bond angle is 96.3°.

(F) CH₄ molecule

The number of atoms bonded to C = 4

Number of lone pairs on C = 0

Therefore, the shape of CH₄ molecule is tetrahedral and the H-C-H bond angle is 109.5°.

7 0

3 years ago

10.

Andru [333]

Answer: 1.8 moles Fe and 2.7 moles $CO_2$ are produced.

Explanation:

The balanced chemical reaction is:

$Fe_2O_3+3CO\rightarrow 2Fe+3CO_2$

According to stoichiometry :

3 moles of $CO$ require 1 mole of $Fe_2O_3$

Thus 2.7 moles of $CO$ will require= $\frac{1}{3}\times 2.7=0.9moles$ of $Fe_2O_3$

Thus $CO$ is the limiting reagent as it limits the formation of product and $Fe_2O_3$ is the excess reagent.

As 3 moles of $CO$ give = 2 moles of $Fe$ and 3 moles of $CO_2$

Thus 2.7 moles of $CO$ will give = $\frac{2}{3}\times 2.7=1.8moles$ of $Fe$ and $\frac{3}{3}\times 2.7=2.7moles$ of $CO_2$

Thus 1.8 moles Fe and 2.7 moles $CO_2$ are produced.

7 0

2 years ago

Gaseous ethane will react with gaseous oxygen to produce gaseous carbon dioxide and gaseous water . Suppose 2.7 g of ethane is m

Bond [772]

Answer:

$m_{H_2O}=4.86gH_2O$

Explanation:

Hello,

In this case, the described chemical reaction is:

$C_2H_6+\frac{7}{2} O_2\rightarrow 2CO_2+3H_2O$

Thus, for the given reacting masses, we must identify the limiting reactant for us to determine the maximum mass of water that could be produced, therefore, we proceed to compute the available moles of ethane:

$n_{C_2H_6}=2.7gC_2H_6*\frac{1molC_2H_6}{30gC_2H_6} =0.09molC_2H_6$

Next, we compute the moles of ethane consumed by 13.0 grams of oxygen by using the 1:7/2 molar ratio between them:

$n_{C_2H_6}^{consumed\ by \ O_2}=13.0gO_2*\frac{1molO_2}{32gO_2}*\frac{1molC_2H_6}{\frac{7}{2} molO_2}=0.116molC_2H_6$

Thus, we notice there are less available moles of ethane, for that reason, it is the limiting reactant, thereby, the maximum amount of water is computed by considering the 1:3 molar ratio between ethane and water:

$m_{H_2O}=0.09molC_2H_6*\frac{3molH_2O}{1molC_2H_6} *\frac{18gH_2O}{1molH_2O} \\\\m_{H_2O}=4.86gH_2O$

Best regards.

3 0

3 years ago