All categories

3 years ago

All substances freeze at the same temperature, so they all have exactly the

Chemistry

1 answer:

Anastasy [175]3 years ago

6 0

Answer:

I think it would be false

Explanation:

All things have a unique freezing/melting point

You might be interested in

How many milliliters of a 0.1000 M NaOH solution would be needed to neutralize a 1.0000-g sample of potassium hydrogen phthalate

7nadin3 [17]

Answer: 2) 2HCl(sq) + CaCO3(s) CaCl2(sq) + CO2(g) + H2O (l) No of moles of CaCO3 = amount of the CaCO3 (g)/mw of CaCO3 (g/mole)= 0.8085 g/100 g/mole = 0.008085

Explanation:

7 0

2 years ago

I NEED HELP PLEASE, THANKS! :)

vaieri [72.5K]

Answer:

This process is known as doping. It can be done by adding either of two types of impurity to the crystal.

(A) By adding electron rich impurities i.e., group 15 elements to the silicon and germanium of group 14 elements.

hope it's helpful

8 0

3 years ago

Ammonia, nh3, for fertilizer is made by causing hydrogen and nitrogen to react at high temperature and pressure. How many moles

charle [14.2K]

Answer:

$0.30molNH_3$

Explanation:

Hello there!

In this case, since the reaction for the formation of ammonia is:

$3H_2+N_2\rightarrow 2NH_3$

We can evidence the 1:2 mole ratio of nitrogen gas to ammonia; therefore, the appropriate stoichiometric setup for the calculation of the moles of the latter turns out to be:

$0.15molN_2*\frac{2molNH_3}{1molN_2}$

And the result is:

$0.30molNH_3$

Best regards!

7 0

3 years ago

An atom is a small building block that forms matter. Many different models of an atom have been made over the years. Which of th

puteri [66]

Answer:

The correct option is A) The atom has changed over the years.

Explanation:

Option A is not correct because an atom does not change. It remains the same always. The structure of an atom will always contain neutrons, protons and electrons.

Scientific theories tend to change over time as new information is brought up. Novel techniques lead to more advanced experiments and results. As a result, a scientific theory is subjected to change whenever evidence is found for a new theory which challenges the older one.

The atomic theory has changed many times due to novel scientific techniques and experiments.

8 0

3 years ago

200.0 mL of 3.85 M HCl is added to 100.0 mL of 4.6 M barium hydroxide. The reaction goes to completion. What is the concentratio

Ede4ka [16]

Answer:

2.387 mol/L

Explanation:

The reaction that takes place is:

2HCl + Ba(OH)₂ → BaCl₂ + 2H₂O

First we calculate how many moles of each reagent were added:

HCl ⇒ 200.0 mL * 3.85 M = 203.85 mmol HCl

Ba(OH)₂ ⇒ 100.0 mL * 4.6 M = 460 mmol Ba(OH)₂

460 mmol of Ba(OH)₂ would react completely with (2*460) 920 mmol of HCl. There are not as many mmoles of HCl so Ba(OH)₂ will remain in excess.

Now we calculate how many moles of Ba(OH)₂ reacted, by converting the total number of HCl moles to Ba(OH)₂ moles:

203.85 mmol HCl * $\frac{1mmolBa(OH)_{2}}{2mmolHCl}$ = 101.925 mmol Ba(OH)₂

This means the remaining Ba(OH)₂ is:

460 mmol - 101.925 mmol = 358.075 mmoles Ba(OH)₂

There are two OH⁻ moles per Ba(OH)₂ mol:

OH⁻ moles = 2 * 358.075 = 716.15 mmol OH⁻

Finally we divide the number of OH⁻ moles by the total volume (100 mL + 200 mL):

716.15 mmol OH⁻ / 300.0 mL = 2.387 M

So the answer is 2.387 mol/L

7 0

3 years ago