A civil engineer designs mostly:

Complete this sentence. If mass remains the same while the volume of a substance ________, the density of the substance will____

Andre45 [30]

If mass remains the same while the volume of a substance increases, the density of the substance will decrease. The increase in the volume is called expansion, while the decrease in the volume is called contraction.
The density measures how much matter (mass) there is in a given amount of space (volume). So, if the mass stays the same and the volume increases then there is the same amount of mass ad before but in bigger volume so the density is decreased.

4 0

3 years ago

Read 2 more answers

How many milliliters of a 0.184 m lino3 solution contain 0.113 moles of lino3?

Bogdan [553]

To determine the volume of LiNO3 present in 0.184 M LiNO3 solution, first note that the concentration of LiNO3 is expressed in units of molarity or moles per liter solution. Thus, given the molarity, 0.184 M, and the number of moles, 0.113 mol LiNO3, the volume of LiNO3 in milliliters can then be determined using this equation:

0.113 mol LiNO3/0.184 mol/L x 1000 mL/L = 614.13 mL LiNO3

7 0

4 years ago

The boiling point of water is 100.0°C at 1 atmosphere. How many grams of sodium acetate (82.04 g/mol), must be dissolved in 283.

Alecsey [184]

Answer:

I have to weight 10,04 g of acetate sodium

Explanation:

This is the colligative propertie about elevation of boiling point

ΔT = Kb . m . i

ΔT is the difference between T° at boiling point of the solution - T° at boiling point of the solvent pure - we have this data 0,450°C

Kb means ebulloscopic constant (0,52 °C.kg/m .- a known value for water)

m means molality (moles of solute in 1kg of solvent)

i means theVan 't Hoff factor (degree of dissociation for a compound)

For the sodium acetate is 2

NaCH3COO ---> Na+ + CH3COO-

0,450°C = 0,52°C.kg/m . m . 2

0,450°C / (0,52°C.kg/m . 2) = m

0,432 m/kg = m

This number means I have 0,432 moles of acetate sodium, my solute in 1kg of water, my solvent. But I don't have 1000 g (1kg) I only have 283 g so let's make the rule of three:

1000 g _____ 0,432 moles

283 g ______ (283g .0,432m) / 1000g = 0,122 moles

Now that I have the moles of acetate sodium, I have to find the mass.

Moles . molar mass = mass

0,122 moles . 82.04 g/mol = 10,04 g

3 0

4 years ago

Read 2 more answers

Calculate the number of moles of aluminum, sulfur, and oxygen atoms in 4.00 moles of aluminum sulfate, al2(so4)3. express the nu

bagirrra123 [75]

To calculate the number of moles of aluminum, sulfur, and oxygen atoms in 4.00 moles of aluminum sulfate, al2(so4)3. We will simply inspect the "number" of aluminum, sulfur, and oxygen atoms available per one mole of the compound. Here we have Al2(SO4)3, which means that for every mole of aluminum sulfate, there are 2 moles of aluminum, 3 (1 times 3) moles of sulfur, and 12 (4x3) moles of oxygen. Since we have four moles of Al2(SO4)3 given, we simply multiply 4 times the moles present per 1 mole of the compound. So we have 4x2 = 8 moles of Al, 4x3 = 12 moles of sulfur, and 4x12 = 48 moles of oxygen.

So the answer is:
8,12,48

3 0

3 years ago

Read 2 more answers

Why does electronegativity decrease from right to left within a period?

hram777 [196]

Because as you move from right to left in a period the elements have less valence electrons. As valence electrons get less in number, the electronegativity decreases.

3 0

3 years ago

Read 2 more answers