What is the number of molecules in 500cm? of oxygen under room conditions?

What is an echo? (1 point)

zaharov [31]

Answer:

The reflection of sound waves

Explanation:

An echo is a reflection of sound that bounces of of one thing to another.

4 0

3 years ago

Read 2 more answers

Please help me i keep getting this wrong :(

solmaris [256]

A) A chandelier has been hanging in the kitchen for years
B) A log floats on top of the lake
C) You place your book on the top of a flat table

Those are the answers. In each case, there is always a force that balances the weight of the object and keeps them in a static equilibrium. Tension, Buoyancy and Normal force.

7 0

3 years ago

How many grams of aluminum are required to react with 35 mL of 2.0 M hydrochloric acid, HCl?__ HCl + __ Al --> __ AlCl3 + __

kiruha [24]

Answer:

0.6258 g

Explanation:

To determine the number grams of aluminum in the above reaction;

determine the number of moles of HCl
determine the mole ratio,
use the mole ratio to calculate the number of moles of aluminum.
use RFM of Aluminum to determine the grams required.

Moles of HCl

35 mL of 2.0 M HCl

2 moles of HCl is contained in 1000 mL

x moles of HCl is contained in 35 mL

$x \: mol \: = \: \frac{2 \: \times \: 35}{1000} \\ = 0.07 \: moles \:$

We have 0.07 moles of HCl.

Mole ratio

Balanced equation

6HCl(aq) + 2Al(s) --> 2AlCl3(aq) + 3H2(g)

Hence mole ratio = 6 : 2 (HCl : Al

but moles of HCl is 0.07, therefore the moles of Al;

$= \frac{2}{6} \times 0.07 \\ \: = 0.0233333 \: moles$

Therefore we have 0.0233333 moles of aluminum.

Grams of Aluminum

We use the formula;

$grams \: = moles \: \times \: rfm$

The RFM (Relative formula mass) of aluminum is 26.982g/mol.

Substitute values into the formula;

$= 0.0233333 \: moles \: \times \: 26.982 \: \frac{g}{mol} \\ = 0.625799 \: grams$

The number of grams of aluminum required to react with HCl is 0.6258 g.

3 0

2 years ago

The main function of a producer in an ecosystem is

jok3333 [9.3K]

Answer:

A producer is a plant or fungi but it mainly is a organism that produces food for a primary consumer

Explanation:

5 0

3 years ago

Match the following descriptions with the correct polysaccharide, note if you answer any part of this question incorrectly a sig

Ad libitum [116K]

Answer:

Glycogen. Cellulose. Amylose. Cellulose. Amylopetin and Glycogen. Amylopetin and Cellulose.

Explanation:

Glycogen is the form that glucose is stored in human body.

Cellulose is the structural part of plant cell walls and human cannot digest it.

Amylose is the polysaccharide linked mainly by the the bonds of $\alpha$ 1,4 glycosidic.

Cellulose is an unbranched polysaccharide linked mainly by the bonds of $\beta$ 1,4 glycosidic.

Amylopetin and Glycogen are branched polysaccharides linked by the bonds of $\alpha$ 1,4 glycosidic and $\alpha$ 1,6 glycosidic.

Amylopetin and Cellulose are mainly stored in plants.

4 0

3 years ago