Strontium

Strontium is used in fireworks to produce a bright red color when ignited. It is commonly used in combination with other metal salts to create an array of vibrant hues in fireworks displays.

You can create a model of a strontium atom by using different colored pom poms to represent protons, neutrons, and electrons. The nucleus can be represented by a larger pom pom with smaller pom poms surrounding it to depict electrons in different energy levels. You can also use toothpicks or pipe cleaners to show the arrangement of the electrons in their orbits around the nucleus.

Mercury oxides are: HgO and Hg2O.

They have "ium" in their name.

No, strontium is not isoelectronic with krypton. Strontium has an atomic number of 38, which means it has 38 electrons, while krypton has an atomic number of 36 and has 36 electrons. Isoelectronic species possess the same number of electrons, so while strontium can lose two electrons to achieve a configuration similar to that of krypton, they are not isoelectronic in their neutral states.

The core electronic configuration of strontium (Sr), which has an atomic number of 38, is represented as [Kr] 5s². This indicates that after the noble gas krypton (Kr), strontium has two additional electrons in the 5s subshell. Consequently, the electron configuration highlights that strontium is an alkaline earth metal, characterized by having two valence electrons in its outermost shell.

The solubility product constant (Ksp) of strontium nitrate (Sr(NO3)2) represents the equilibrium constant for the dissolution of the salt in water. The dissolution can be expressed as: Sr(NO3)2 (s) ⇌ Sr²⁺ (aq) + 2 NO3⁻ (aq). The Ksp expression for this equilibrium is given by Ksp = [Sr²⁺][NO3⁻]². While the exact value of Ksp for strontium nitrate is not commonly referenced, it is typically quite high, indicating that strontium nitrate is highly soluble in water.

The reaction between strontium oxalate and water produces strontium oxalate solution. The balanced chemical equation for this reaction is SrC2O4 (s) + H2O (l) → SrC2O4•nH2O (aq), where n is the number of water molecules that coordinate with strontium oxalate in the resulting solution.

The time it takes for the radiation level of strontium to drop to one-sixteenth of its original level can be determined using its half-life. For strontium-90, which has a half-life of about 29 years, it would take four half-lives for the radiation to decrease to one-sixteenth (since (1/2^4 = 1/16)). Therefore, it would take approximately 116 years for the radiation level of strontium-90 to drop to one-sixteenth of its original level.

Yes, strontium is larger than a calcium atom. Strontium has a higher atomic number (38) compared to calcium (20), which means it has more electron shells. This additional shell increases the size of the strontium atom, resulting in a larger atomic radius than that of calcium.

An atom of strontium has 38 electrons, which are distributed across different electron shells based on the aufbau principle and the rules of electron configuration. Strontium, with an atomic number of 38, has electrons filling up to the fifth energy level or electron shell. Therefore, there are five electron shells containing electrons in an atom of strontium.

Strontium primarily exhibits ionic character due to its position as an alkaline earth metal, which tends to lose its two valence electrons easily to form Sr²⁺ ions. However, in certain circumstances, strontium can exhibit some covalent character, especially when it forms compounds with highly electronegative elements, where there is a degree of electron sharing. Nevertheless, this covalent character is generally weak compared to more covalent compounds formed by nonmetals. Overall, strontium's behavior is predominantly ionic.

Strontium hydroxide is typically sourced from the reaction between strontium oxide and water, producing strontium hydroxide. It can also be produced as a byproduct in the refining of strontium-containing ores or as a commercial product from chemical suppliers.

Strontium was first discovered by Scottish chemist Adair Crawford in 1790 while analyzing a sample of a mineral called strontianite, which is named after the Scottish village of Strontian where the mineral was originally found. The element was later isolated and identified by the Scottish chemist Thomas Hope in 1792.

Both are situated in the group 2 of the periodic table.

The maximum density in this list: radium with 5,50 g/cm3.

2

The net ionic equation for strontium hydroxide (Sr(OH)2) and iron sulfate (FeSO4) is:

Sr(OH)2(aq) + Fe^2+(aq) → Sr^2+(aq) + Fe(OH)2(s)

This reaction shows the formation of a precipitate, iron(II) hydroxide, which is insoluble and therefore precipitates out of the solution.

Strontium nitrate and ammonium carbonate are both easily soluble in water.

1.) a.) Because of shielding, there are only 7 of the 17 protons of the Cl nucleus to hold the 3s2 3p5 electrons of Cl. With the gain of an electron, those 7 protons have to hold on to 8 electrons. The attraction is weaker, so Cl- is larger. In K+, there is one less electron, the 4s is empty, so K+ is smaller.

b.) Li is 1s2 2s1. The energy to remove the 2s1 is low, but the energy to remove the second electron from a filled shell is very high. Be is 1s2 2s2. The 1s2 is a filled shell, but the 2s2 is not. The energy to remove the first electron is low. The energy to remove the second is higher but not extremely high.

2.) a.) This is beyond me.

b.) Blue light is shorter in wavelength and higher in frequency than red light, so red light is less energetic.

3.) a.) All the same. "Equal volumes of gas contain equal numbers of molecules." --Avogadro.

b.) Molecular weights: NH3=17, NO2=46, N2=28. So the lightest molecules, NH3, are the fastest.

c.) This is beyond me.

4.) Decreasing the volume (by moving the piston) increases the pressure. Reducing the temperature by 20C = 20K decreases the pressure. You did not specify the new volume, so the final pressure cannot be calculated.

5.) a.) 2Na(s) + 2H2O ===> 2NaOH(aq) + H2(g)

b.) There are not enough data given to calculate.

c.) Because one cannot calculate /\H per g or per mole in b.), this cannot be calculated either.

d.) 17C = 290K, so 6.50LH2 x 740mmHg/760mmHg x 290K/273K = 6.72 L H2. You can also work this out with P1V1/T1 = P2V2/T2 or P2 = P1V1T2/V2T1

6.) a.) 1s2 2s2 2p6 3s2 3p6 4s2 3d2

b.) 3 2 -2 -1/2 and 3 2 -1 -1/2

c.) 1s2 2s2 2p6 3s2 3p6 3d2 Answer this question…