All categories

3 years ago

How many significant figures are in the measurement 811.40 grams?

Chemistry

2 answers:

Llana [10]3 years ago

8 0

Answer:

There is 5 significant figures in 811.40 grams

Explanation:

The significant figures are units that can be taking into account to write a figure.

Exists two general rules for it:

1. The numbers including zero (0) that are to the right of the figure are counted as a significant figure example: 345.60 has 5 significant figures

2. The zero (0) that are to the left of the figure are NOT counted as a significant figure example: 0.005 has 1 significant figure

igomit [66]3 years ago

3 0

There are 5 significant figures in this number because the zero counts and it comes after a number and on the right of the decimal point

You might be interested in

You have been given two samples of water. One is from the atlantic ocean and the other is from lake superior. Describe how you w

lbvjy [14]

Answer:

i think by their salinity (the saltiness or amount of salt dissolved in a body of water)

Explanation:

Water salinity is measured by passing an electric current between the two electrodes of a salinity meter in a sample of water.

5 0

2 years ago

__ SnCl4 → __ Sn + __ Cl2

Kisachek [45]

Answer:

Sn (s) + 2 Cl2 (g) → SnCl4 (l)

This is an oxidation-reduction (redox) reaction:

4 Cl0 + 4 e- → 4 Cl-I

(reduction)

Sn0 - 4 e- → SnIV

(oxidation)

Cl2 is an oxidizing agent, Sn is a reducing agent.

Reactants:

Names: Tin source: wikidata, accessed: 2019-09-07source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Sn source: wikidata, accessed: 2019-09-07, Element 50 source: wikidata, accessed: 2019-09-07

Appearance: White crystalline powder source: ICSC, accessed: 2019-09-04; Gray to almost silver-white, ductile, malleable, lustrous solid. source: NIOSH NPG, accessed: 2019-09-02

Cl2

Names: Chlorine source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Molecular chlorine source: NIOSH NPG, accessed: 2019-09-02

Appearance: Greenish-yellow compressed liquefied gas with pungent odour source: ICSC, accessed: 2019-09-04; Greenish-yellow gas with a pungent, irritating odor. [Note: Shipped as a liquefied compressed gas.] source: NIOSH NPG, accessed: 2019-09-02

Products:

SnCl4 – Tetrachlorostannane source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02, Tin tetrachloride source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Tin(IV) chloride source: wikipedia, accessed: 2019-09-28

Other names: Stannic chloride source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Tin(iv) chloride (anhydrous) source: ICSC, accessed: 2019-09-04

Appearance: Colorless to slightly yellow fuming liquid source: wikipedia, accessed: 2019-09-28; Colourless or slightly yellow fuming liquid with pungent odour source: ICSC, accessed: 2019-09-04

6 0

2 years ago

22.4l of ammonia is reaxts with 1.406 mole of oxygen to produce NO and h2o .1.what volume of no is produced at ntp

IceJOKER [234]

Answer:

The volume of NO is 22.4L at STP

Explanation:

Based on the reaction:

2NH3 + 5/2O2 → 2NO + 3H2O

2 moles of NH3 react with 5/2 moles of O2 to produce 2 moles of NO.

To solve this question, we need to find the moles of each reactant in order to find the limiting reactant as follows:

Moles NH3 -Molar mass: -17.01g/mol-

Using PV = nRT

PV/RT = n

Where P is pressure = 1atm at STP

V is volume = 22.4L

R is gas constant = 0.082atmL/molK

T is absolute temperature = 273.15K

1atm*22.4L/0.082atmL/molK*273.15K = n

n = 1.00 moles of NH3

For a complete reaction of 1.00 moles of NH3 are needed:

1.00 moles NH3 * (5/2moles O2 / 2moles NH3) = 1.25 moles of O2

As there are 1.406 moles of O2, the limiting reactant is NH3

The moles of NO produced are the same than moles of NH3 because 2 moles of NH3 produce 2 moles of NO. The moles of NO are 1.00 moles

And as 1.00moles of gas are 22.4L at STP:

<h3>The volume of NO is 22.4L at STP</h3>

4 0

2 years ago

What is a half-life of an isotope? please help

N76 [4]

Answer:

Explanation:

Hello! Hope this helps!

One important measure of the rate at which a radioactive substance decays is called half-life, or t1/2. Half-life is the amount of time needed for one half of a given quantity of a substance to decay. Half-lives as short as 10–6 second and as long as 109 years are common.

3 0

3 years ago

The use of crucible

Norma-Jean [14]

a ceramic or metal container in which metals or other substances may be melted or subjected to very high temperatures.

"the crucible tipped and the mold filled with liquid metal"

a situation of severe trial, or in which different elements interact, leading to the creation of something new.

"their relationship was forged in the crucible of war"

3 0

3 years ago