How many inches are in 2.0 miles

Cells, Cell Division)

zalisa [80]

Answer:

c is wrong

Explanation:

8 0

3 years ago

Based on the passage , where in the United States would a physician encounter the most cases of SAD ?

Montano1993 [528]

Answer/Explanation:

We cannot see the passage, but SAD stands for Seasonal Affective Disorder. SAD is a type of depressive disorder related to lack of light, and therefore changes with the seasons. It is a severe version of the "winter blues"

In the winter months, where the days are shorter, individuals who suffer from SAD suffer from mood changes. They get depressed, have a reduction in energy levels, and withdraw socially. They may also gain weight. This causes problems with relationships, work, and school.

Since SAD is linked to light, SAD is likely more common in the Northern areas of the United States, where winter days are shorter.

7 0

3 years ago

A pharmacist wishes to strengthen a mixture from 10%alcohol to 30% alcohol. How much pure alcohol should be added to 7 liters of

Tomtit [17]

Answer:

2 litres of pure alcohol will be added to make the overall concentration of 9 litres of mixture as 30%.

Explanation:

Suppose x is the number of litres added to the 10% mixture than the quantity of new mixture is given as below

$n_{old}=7$ litres
$n_{new}=7+x$ litres

Also the quantity of alcohol is given as

$q_{old}=10 \% \, of \, 7 \, litres =0.7$

$q_{added}=x$

$q_{new}= 30 \% \,of \,new\, quantity = 0.3(7+x)$

Now the equation is as

$q_{old}+q_{added}=q_{new}\\0.7+x=0.3(7+x)\\0.7+x=2.1+0.3x\\x-0.3x=2.1-0.7\\0.7x=1.4\\x=2 \, litres$

So 2 litres of pure alcohol will be added to make the overall concentration of 9 litres of mixture as 30%.

8 0

3 years ago

An important reaction that takes place in a blast furnace during the production of iron is the formation of iron metal and CO2 f

ladessa [460]

Answer: Mass of $Fe_2O_3$ required to form 930 kg of iron is 1328 kg

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

For iron:

Given mass of iron = 930 kg = 930000 g (1kg=1000g)

Molar mass of iron = 56 g/mol

Putting values in equation 1, we get:

$\text{Moles of iron}=\frac{930000g}{56g/mol}=16607mol$

The chemical equation for the production of iron follows:

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

By Stoichiometry of the reaction:

2 moles of iron are produced by = 1 mole of $Fe_2O_3$

So, 16607 moles of iron will be produced by = $\frac{1}{2}\times 16607=8303moles$ of $Fe_2O_3$

Now, calculating the mass of $Fe_2O_3$ from equation 1, we get:

Mass of $Fe_2O_3$ = $moles\times {\text {molar mass}}=8303\times 160=1328480g=1328kg$

Thus mass of $Fe_2O_3$ required to form 930 kg of iron is 1328 kg

6 0

3 years ago

How does the comic strip define a polar molecule

zmey [24]

The answer is: A molecule with a difference in electrical charge between two ends.

Electronegativity (χ) is a property that describes the tendency of an atom to attract a shared pair of electrons.

Atoms with higher electronegativity attracts more electrons towards it, electrons are closer to that atom.

For example fluorine has electronegativity approximately χ = 4 and oxygen χ = 3,5, fluorine attracts electron and he has negative charge and oxygen has positive charge.

4 0

3 years ago