That's why rubbing your hands together makes them warmer. ... Friction causes the molecules on rubbing surfaces to move faster, so they have more energy. This gives them a higher temperature, and they feel warmer. Heat from friction can be useful.

3 0

2 years ago

Molarity to percent by mass. Convert 1.672 mol/L MgCl2(aq) solution to percent by mass of MgCl2 in the solution. The solution de

nignag [31]

Answer:

$\%m/m=14\%$

Explanation:

Hello!

In this case, since the molarity of magnesium chloride (molar mass = 95.211 g/mol) is 1.672 mol/L and we know the density of the solution, we can first compute the concentration in g/L as shown below:

$[MgCl_2]=1.672\frac{molMgCl_2}{L}*\frac{95.211gMgCl_2}{1molMgCl_2}=159.2\frac{gMgCl_2}{L}$

Next, since the density of the solution is 1.137 g/mL, we can compute the concentration in g/g as shown below:

$[MgCl_2]=159.2\frac{gMgCl_2}{L}*\frac{1L}{1000mL}*\frac{1mL}{1.137g}=0.14$

Which is also the by-mass fraction and in percent it turns out:

$\%m/m=0.14*100\%\\\\\%m/m=14\%$

Best regards!

6 0

2 years ago

Solve the radical equation. what is the extraneous solution to the radical equation? the solution -1 is an extraneous solution.

Arada [10]

Answer:

X = 7

Explanation:

4 0

1 year ago

4.5cm wide by 5.750cm long by 1.50cm tall what is the volume of the box

Anni [7]

Answer:

volume of box is 38.81 cm³.

Explanation:

Given data:

Width of box = 4.5 cm

Height of box = 5.750 cm

Length of box = 1.50 cm

Solution:

Formula:

Volume = length × height × width

by putting values,

V = 1.50 cm × 5.750 cm× 4.5 cm

V = 38.81 cm³

Thus, the volume of box is 38.81 cm³.

5 0

2 years ago