Witch organism is primary consumers? O krill O elephant seal O squid O penguins

A solution is prepared by dissolving 15.0 g of nh3 in 250.0 g of water. the density of the resulting solution is 0.974 g/ml. the

sergeinik [125]

The formula for molality---> m = moles solute/ Kg of solvent

the solute here is NH₃ because it's the one with less amount. which makes water the solvent.

1) let's convert the grams of NH₃ to moles using the molar mass

molar mass of NH₃= 14.0 + (3 x 1.01)= 17.03 g/ mol

15.0 g (1 mol/ 17.03 g)= 0.881 mol NH₃

2) let's convert the grams of water into kilograms (just divide by 1000)

250.0 g= 0.2500 kg

3) let's plug in the values into the molality formula

molality= mol/ Kg---> 0.881 mol/ 0.2500 kg= 3.52 m

6 0

3 years ago

Sound energy is caused by ___

sergey [27]

Sound energy is produced when an object vibrates. The sound vibrations cause waves of pressure that travel through a medium, such as air, water, wood or metal. Sound energy is a form of mechanical energy. (I believe this is it)

3 0

3 years ago

Air at 293 K and 750 mm Hg pressure has a relative humidity of 80%. What is its percent humidity? The vapour pressure of water a

Mekhanik [1.2K]

Answer : The correct option is, (c) 79.62

Explanation :

The formula used for percent humidity is:

$\text{Percent humidity}=\text{Relative humidity}\times \frac{p-p^o_v}{p-p_v}\times 100$ ..........(1)

The formula used for relative humidity is:

$\text{Relative humidity}=\frac{p_v}{p^o_v}$ ...........(2)

where,

$p_v$ = partial pressure of water vapor

$p^o_v$ = vapor pressure of water

p = total pressure

First we have to calculate the partial pressure of water vapor by using equation 2.

Given:

$p=750mmHg$

$p^o_v=17.5mmHg$

Relative humidity = 80 % = 0.80

Now put all the given values in equation 2, we get:

$0.80=\frac{p_v}{17.5mmHg}$

$p_v=14mmHg$

Now we have to calculate the percent humidity by using equation 1.

$\text{Percent humidity}=0.80\times \frac{750-17.5}{750-14}\times 100$

$\text{Percent humidity}=79.62\%$

Therefore, the percent humidity is 79.62 %

4 0

3 years ago

Avanti works in a bookstore. She has four books and is going to place them in two stacks. The diagram above shows the books befo

Feliz [49]

Answer:

Well they didn't transfer any energy when they weren’t touching and it did t produce any energy if it didn’t move. Since they are on top of each other they are causing momentum on each other creating kinetic energy

Explanation:

3 0

2 years ago

Explain why the elements of groups 1 and 7 are mostly used in the form of compound

docker41 [41]

Group 1 and group 7 of element group consists of alkali metal, which are generally combined with other elements in nature, so they have properties of compound

8 0

2 years ago