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3 years ago

Choose all that apply. Which of the following are not considered to be elements essential for life?

Chemistry

2 answers:

Basile [38]3 years ago

8 0

Al, Si, Mg
All other elements seem more necessary in life

Advocard [28]3 years ago

4 0

aluminum and silicon are not essential for life

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the chemical formula for copper iodide is Cul. How many atoms of copper(Cu) is it made from? How many atoms of iodine(I)?

Alexandra [31]

<span>The molecule contains one atom of copper and one atom of iodine. They are connected by an ionic bond because the copper takes a positive charge and the iodine has a negative charge before they are bonded. These opposing charges are negated when the two elements come together.</span>

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3 years ago

A mixture of methanol and methyl acetate contains 15.0 wt% methanol.

Usimov [2.4K]

The mixture flow rate in lbm/h = 117.65 lbm/h

<h3>Further explanation</h3>

Given

15.0 wt% methanol

The flow rate of the methyl acetate :100 lbm/h

Required

the mixture flow rate in lbm/h

Solution

mass of methanol(CH₃OH, Mw= 32 kg/kmol) in mixture :

$\tt 15\%\times 200~kg=30~kg\\\\mol=\dfrac{mass}{MW}=\dfrac{30~kg}{32~kg/kmol}=0.9375~kmol$

mass of the methyl acetate(C₃H₆O₂,MW=74 kg/kmol,85% wt) in 200 kg :

$\tt 85\%\times 200=170~kg\\\\mol=\dfrac{170}{74}=2.297~kmol$

Flow rate of the methyl acetate in the mixture is to be 100 lbm/h.

1 kg mixture = 0.85 .methyl acetate

So flow rate for mixture :

$\tt \dfrac{1~kg~mixture}{0.85~methyl~acetat}\times 100~lbm/h=117.65~lbm/h$

5 0

3 years ago

Which of the following best explains why the oceanic crust is youngest at the oceanic ridges?

murzikaleks [220]

Answer:

the different depths of the ocean

5 0

3 years ago

Read 2 more answers

Consider a closed containing a solid in equilibrium with its vapor. The volume of the solid is much less than that of the contai

Furkat [3]

Answer:

Explanation:

check the attachment below

5 0

3 years ago

Calculate the amount of heat required to completely sublime 55.0 g of solid dry ice CO2 at its sublimation temperature. The heat

aliina [53]

Answer:

40.4 kJ

Explanation:

Step 1: Given data

Mass of CO₂ (m): 55.0 g

Heat of sublimation of CO₂ (ΔH°sub): 32.3 kJ/mol

Step 2: Calculate the moles corresponding to 55.0 g of CO₂

The molar mass of CO₂ is 44.01 g/mol.

n = 55.0 g × 1 mol/44.01 g = 1.25 mol

Step 3: Calculate the heat (Q) required to sublimate 1.25 moles of CO₂

We will use the following expression.

Q = n × ΔH°sub

Q = 1.25 mol × 32.3 kJ/mol = 40.4 kJ

7 0

2 years ago