All categories

2 years ago

PLEASEEEE HELP :')

Chemistry

1 answer:

mel-nik [20]2 years ago

7 0

Answer:

340 grams Ca₃P₂ (2 sig. figs.)

Explanation:

3Ca + 2P => Ca₃P₂

5.6 mole + excess => ? grams

Convert the 'known' to a coefficient of 1 by dividing all coefficients by 3.

=> Ca + 2/3P => 1/3Ca₃P₂

From the above, 1 mole of Ca => 1/3 mole Ca₃P₂

∴ 5.6 mole Ca in an excess of P => 1/3(5.6 mole) Ca₃P₂

=> 1.8666 mol Ca₃P₂ (calculator answer) ≅ 1.9 mol Ca₃P₂

=> 1.9 mole x 182 g Ca₃P₂/mol Ca₃P₂ = 339.73333 grams Ca₃P₂

≅ 340 grams Ca₃P₂ (2 sig. figs.)

You might be interested in

How might a theory relate to a model

oksian1 [2.3K]

These are related but can be independent, because it is possible to, the theories are studied in mathematical logic, especially in model theory

8 0

3 years ago

Draw structures from the following names, and determine which compounds are optically active:(b) 3-chloro-2,2,5-trimethylhexane

inn [45]

The given compound 3-chloro-2,2,5-trimethylhexane is an optically active compound .

Because this compound does not have plane of symmetry (POS) and center of symmetry (COS) i.e. does not have di-symmetry . And also forms non superimposable mirror image . the compound is optically active .

It has chiral center.

Here the chiral carbon has 4 distinct groups such as : chlorine , hydrogen , 2-methylpropyl , tertbutyl .

<h3>What is di-symmetry?</h3>

Di-symmetry is that which have no center of symmetry and plane of symmetry and alternate axis of symmetry .

<h3>Chiral center :</h3>

Have Sp3 hybridized center (4sigma bond ) .

4 distinct group is attached to the chiral atom. form non -superimposable mirror image .

<h3>What is optical isomerism ?</h3>

Same molecular formula and same structural formula . also have same physical and chemical properties .

They differ in their behavior towards plane polarized light (ppl) .

Learn more about chiral center here:

brainly.com/question/9522537

#SPJ4

7 0

1 year ago

A sample of octane undergoes combustion according to the equation 2 C8H18 + 25 O2 → 16 CO2 + 18 H2O ΔH°rxn = -11018 kJ. What mas

Anna71 [15]

Answer:

$\large \boxed{\text{528.7 g} }$

Explanation:

It often helps to write the heat as if it were a reactant or a product in the thermochemical equation.

Then you can consider it to be 11018 "moles" of "kJ"

We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.

M_r: 32.00

2C₈H₁₈ + 25O₂ ⟶ 16CO₂ + 8H₂O + 11 018 kJ

n/mol: 7280

1. Moles of O₂

The molar ratio is 25 mol O₂:11 018 kJ

$\text{Moles of O}_{2} = \text{7280 kJ} \times \dfrac{\text{25 mol O}_{2}}{\text{11 018 kJ}} = \text{16.52 mol O}_{2}$

2. Mass of O₂

$\text{Mass of C$_{8}$H}_{18} = \text{16.52 mol O}_{2} \times \dfrac{\text{32.00 g O}_{2}}{\text{1 mol O}_{2}} = \textbf{528.6 g O}_{2}\\\text{The reaction requires $\large \boxed{\textbf{528.67 g O}_{2}}$}$

3 0

2 years ago

The nucleus of the atom is held together by the attraction of the positively charged protons and the negatively charged electron

7nadin3 [17]

False.........................

8 0

2 years ago

Shiny; ductile; solid at room temperature which of the elements best fits the description? hint: look at your periodic table.

avanturin [10]

Take the attached picture of a periodic table as a guide. You are finding for a solid metal. Therefore, streamline your choices by looking at elements written in black bold letters, because they are all solid. Next, if you look at the center, the legend for metals are colors in orange, yellow, flesh, lavender, pink, and cyan blue. These region would be your choices. Next, you want to find a metal that is shiny and ductile. The shiny appearance is a common characteristic of luster by materials. Ductility is the ability of a metal to stretch when under tensile stress. These properties are best exhibited by metals in the transitions metals colored in pink. Therefore, the answer to your question would be any of the metal in the pink area. Examples are Titanium, Chromium, Gold, Silver, Platinum, Tungsten, etc.

6 0

3 years ago