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A cell spends most of its life in this stage of the cell cycle, where it grows and replicates its DNA

Alekssandra [29.7K]

What are u asking there is no specific question

8 0

3 years ago

Convert the density of water, 1.00 g/mL to lb/ft3. Provide only the numerical value in your answer with the correct number of si

PtichkaEL [24]

Answer:

The density of water $1.00 g/ml=62.43 lbs/ft^3$ .

Explanation:

Density of water = 1.00 g/mL

1 lb = 453.592 g

$1 g=\frac{1}{453.592} lbs$

$ft^3=28316.8 mL$

$1 mL=\frac{1}{28316.8} ft^3$

Density of the water in $lb/ft^3$ :

$\frac{1.00 g}{1 mL}=\frac{1.00}{453.592 } lb\times \frac{28316.8 }{1 ft^3}$

$=62.43 lbs/ft^3$

The density of water $1.00 g/ml=62.43 lbs/ft^3$ .

3 0

4 years ago

What is the relationship between a compound and the elements it is made from? (4 points)

Serggg [28]

Answer:

The compound may have properties that are very different from those of the elements.

Explanation:

For example - common salt, sodium chloride ( NaCl) has very different properties from sodium and chlorine

7 0

3 years ago

What is the pH of a 900 mL solution containing 3.40 grams of hydrocyanic acid

Allushta [10]

Answer:

$pH = 5.05$

Explanation:

pH is derived from the concentration of hydronium ions in a solution. Hydrocyanic acid is HCN.

First, we shall figure out the moles of HCN:

$\frac{3.4g}{27.03g/mol} = 0.125786$

If HCN was a strong acid:

HCN has a 1:1 ratio of H+ ions, the moles of H+ is also the same.

To find the molarity, we now divide by Liters. This gets us:

$\frac{0.125786 moles}{0.9L} = 0.139762 M$

Finally, we plug it into the definition of pH:

$pH = -log[H^{+} ]$

$pH = -log(0.139762)$

$pH = 0.855$

However, since HCN is a weak acid, it only partially dissociates. The $K_a$ of HCN is $6.2 * 10^{-10}$ .

$K_a = \frac{[H^+][A^-]}{[HA]}$

We can use an ice table to determine that when x = H+,

$K_a = \frac{x^2}{0.125786-x}$

$[H^+] = 8.83*10^{-6}$

$pH = -log[H^{+} ]$

$pH = -log(8.83 * 10^{-6} )$

$pH = 5.05$

7 0

4 years ago

Balance the chemical equation given below, and determine the number of grams of MgO that are needed to produce 20.0 g of Fe2O3.

Alenkasestr [34]

Answer:

1.) The balanced equation is 3MgO(s) + 2Fe(s) ===> Fe2O3(s) + 3Mg(s)

2.) 20g of Fe2O3 will be produced by 20 ×120/160 = 15g of MgO

Explanation:

THE CORRECT EQUATION IS: MgO(s) + ___ Fe(s) ===> Fe2O3(s) + ___ Mg(s)

The balanced equation is: 3MgO(s) + 2Fe(s) ===> Fe2O3(s) + 3Mg(s)

molar mass of 3MgO = 3(24 + 16) = 120

Molar mass of Fe2O3 = 2 X 56 + 3 X 16

=112 +48 =160

From the equation, 120g of MgO Produced 160g of Fe2O3

Therefore 20g of Fe2O3 will be produced by 20 ×120/160 = 15g of MgO.

7 0

3 years ago