One of the advantages of nylon over rayon is that nylon:

solniwko [45]

An element is the simplest form of a substance. ... An atom is the part of an element. A particular element is composed of only one type of atom. Atoms are further composed of subatomic particles called electrons, protons and neutrons.

5 0

3 years ago

Read 2 more answers

HCI is A) an acid B) a base C) salt D) none

Leona [35]

I think the answer is

A) an acid

8 0

3 years ago

Read 2 more answers

MULTIPLE CHOICE QUESTION

schepotkina [342]

Answer:

(a) The slope of distance-time graph gives the speed of the objects.

As the slope of object (B) is the greatest among all, thus B has the largest speed and hence it is the fastest among all the objects.

(b) : As the curve of the objects do not intersect with each other even once, hence they cannot be at the same point on the road at the same time.

(c) : On the y axis (i.e. distance line), 7 small represents 4 km

∴ 1 small line =

7

4

=0.57 km

Position of C at the instant B passes A is 8 km

(d) ; Position of B at the instant it passes C is 2nd small line above 4 km i.e. 4+2×0.57=5.14 km

∴ Distance traveled by B =5.14−0=5.14 kmV

Explanation:

4 0

3 years ago

A chemistry student weighs out of lactic acid into a volumetric flask and dilutes to the mark with distilled water. He plans to

34kurt

Answer:

28.0mL of the 0.0500M NaOH solution

Explanation:

0.126g of lactic acid diluted to 250mL. Titrated with 0.0500M NaOH solution.

The reaction of lactic acid, H₃C-CH(OH)-COOH (Molar mass: 90.08g/mol) with NaOH is:

H₃C-CH(OH)-COOH + NaOH → H₃C-CH(OH)-COO⁻ + Na⁺ + H₂O

Where 1 mole of the acid reacts per mole of the base.

You must know the student will reach equivalence point when moles of lactic acid = moles NaOH.

the student will titrate the 0.126g of H₃C-CH(OH)-COOH. In moles (Using molar mass) are:

0.126g ₓ (1mol / 90.08g) = 1.40x10⁻³ moles of H₃C-CH(OH)-COOH

To reach equivalence point, the student must add 1.40x10⁻³ moles of NaOH. These moles comes from:

1.40x10⁻³ moles of NaOH ₓ (1L / 0.0500moles NaOH) = 0.0280L of the 0.0500M NaOH =

<h3>28.0mL of the 0.0500M NaOH solution</h3>

8 0

3 years ago

3.15 mol of an unknown solid is placed into enough water to make 150.0 mL of solution. The solution's temperature increases by 1

nordsb [41]

Answer: The enthalpy change of the unknown solid is 3.824 kJ/mol

Explanation:

To calculate the mass of solution , we use the equation:

$\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}$

Density of solution = 1.20 g/mL

Volume of solution = 150.0 mL

Putting values in above equation, we get:

$1.20g/mL=\frac{\text{Mass of solution}}{150.0mL}\\\\\text{Mass of solution}=(1.20g/mL\times 150.0mL)=180g$

The equation used to calculate heat released or absorbed follows:

$Q=m\times c\times \Delta T$

q = heat absorbed or released

m = mass of solution = 180 g

c = specific heat capacity = 4.18 J/g°C

$\Delta T$ = change in temperature = 16.01°C

Putting values in above equation:

$Q=180\times 4.18\times 16.01=12045.9J=12.046kJ$

To calculate the enthalpy change of the reaction, we use the equation

$\Delta H_{rxn}=\frac{q}{n}$

where,

q = amount of heat absorbed = 12.046 kJ

n = number of moles of solid = 3.15 moles

$\Delta H_{rxn}$ = enthalpy change of the reaction

Putting values in above equation, we get:

$\Delta H_{rxn}=\frac{12.046kJ}{3.15mol}=3.824kJ/mol$

Hence, the enthalpy change of the unknown solid is 3.824 kJ/mol

5 0

3 years ago