1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
mamaluj [8]
3 years ago
13

How many electrons does calcium hace?

Chemistry
1 answer:
Alja [10]3 years ago
4 0
The number of electrons is 20. hope this helps
You might be interested in
Calculate the density of mercury of it pours exactly 22.5 mL into a graduated cylinder and has a mass of 316 g.
Rasek [7]
Density = mass/volume = 316/22.5 = 14.045g/mL. 
8 0
3 years ago
A compound contains 64.27% carbon, 7.19% hydrogen, and 28.54% oxygen. the molar mass is 168.19 g/mol. what is the molecular form
coldgirl [10]
Empirical formula is the simplest ratio of whole numbers of components in a compound 
calculating for 100 g of compound 
                                             C                             H                             O
mass                                  64.27 g                   7.19 g                     28.54 g
number of moles        64.27 g / 12 g/mol      7.19 g/1 g/mol     28.54 g / 16 g/mol 
                                        = 5.356 mol           = 7.19 mol           = 1.784 mol 
divide by least number of moles  
                                     5.356 / 1.784            7.19 / 1.784         1.784 / 1.784
                                      = 3.002                     4.03                     = 1.000
rounded off to nearest whole number 
 C - 3
 H - 4
 O - 1
empirical formula - C₃H₄O
 
 mass of empirical formula = 12 g/mol  x 3 + 1 g/mol x 4 + 16 g/mol x 1 = 56 g
molecular mass = 168.19 g/mol 
molecular formula is the actual ratio of elements making up the compound 
number of empirical units = molar mass of molecule / empirical mass
      empirical units = 168.19 g/mol  / 56 g = 3.00
there are 3 empirical units making up the molecular formula 
molecular formula = 3 x C₃H₄O

molecular formula = C₉H₁₂O₃

                 
5 0
4 years ago
Using bond lengths in Table 9.2 (p. 371) and assuming ideal geometry, calculate each of the following distances:
Fed [463]

<u>158 pm</u> is the distance Between equatorial Fluorine atoms in PF₅<u>(</u>Phosphorus pentafluoride).

<h3>What is Fluorine?</h3>

The chemical element fluorine has an atomic number of 9 and the symbol F. The lightest halogen, it is an extremely poisonous, pale yellow diatomic gas under normal conditions. It is exceedingly reactive and, as the most electronegative element, reacts with all other elements with the exception of argon, neon, and helium.

Fluorine is the 24th most abundant element overall and the 13th most abundant on Earth. In order to decrease the melting temperatures of metal ores for smelting, fluorite, the main mineral source of fluorine, was added. The Latin verb fluo, which means "flow," gave the mineral its name. Fluorite was first described in 1529.

Learn more about fluorine

brainly.com/question/24373411

#SPJ4

7 0
2 years ago
Realizar los isomeros geométricos para las siguientes estructuras: 2-hepteno y Ácido 2-butenoico
kramer

Answer:

The cis-trans isomerism (or geometric isomerism ) is a type of stereoisomerism of alkenes and cycloalkanes . A distinction is made between the cis isomer , in which the substituents are on the same side of the double bond or on the same face of the cycloalkane. This is an electronic version in English. [ 1 ]

Their characteristics are:

They both have the same formula.They have different chemical and physical properties.The IUPAC advises against the use of the term geometric isomerism. [ 2 ]

4 0
3 years ago
A student investigated the time taken for amylase to breakdown a 10% starch solution into glucose at
Mandarinka [93]

Answer:

Phenolphthalein is an indicator. It is pink in alkaline solutions and turns colourless as the pH decreases.

It can be used to measure the activity of the enzyme lipase on the breakdown of lipids.

Samples of milk containing phenolphthalein were incubated with lipase at different temperatures.

The time taken for the phenolphthalein to turn colourless was recorded and used to calculate the rate of enzyme activity.

Figure 10 shows these results.

Picture

(a) (i) Explain why phenolphthalein turns colourless when lipase breaks down the lipids in milk. (2)

(ii) Describe the effect of temperature on the activity of lipase, as shown in Figure 10. (2)

(iii) Explain why the activity of lipase changes above a temperature of 40°C. (2)

(b) A student investigated the time taken for amylase to breakdown a 10% starch solution into glucose at 37°C. The student repeated the investigation five times.

7 0
3 years ago
Other questions:
  • How is condensation explained by the Kinetic Molecular Theory? Cooling reduces particle motion, resulting in coalescence by attr
    11·2 answers
  • The major elements of organic molecules is carbon identify three other carbon is normally bonded to
    13·1 answer
  • Which of the following generally results when the Senate and the House of Representatives pass different versions of the same bi
    15·1 answer
  • The veterinarian prescribes the NSAID carprofen for a 50-pound dog with arthritis at a dose of 4.4 mg/kg and would like this dos
    10·1 answer
  • Kaila runs competitively. She would like to calculate her average running speed each time she runs. Which data should Kaila reco
    13·1 answer
  • How many molecules of CaCL2 are equivalent to 75.9g CaCl2
    8·1 answer
  • Need help! Don’t understand
    8·1 answer
  • if you react 28 grams of butene with excess hydrogen how many grams of butane would you expect to get
    12·1 answer
  • Write a mechanism for the esterification of propanoic acid with 18O-labeled ethanol. Show clearly the fate of the 18O label. (b)
    5·1 answer
  • A mole of one element contains _______ number of atoms as a mole of another element.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!