Answer:
the answer i belive is c
Explanation:
A chemical reaction occurs because heat and light are given off.
Explanation:
A property which causes change in chemical composition of a substance is known as a chemical property. For example, reactivity, toxicity, combustion etc.
Whereas a property which causes no change in chemical composition of a substance is known as a physical property. For example, mass, volume, density etc.
Sodium is a very reactive metal and it reacts readily with oxygen, water etc. So, when sodium is added to water then occurrence of an orange flame represents its reactivity.
Thus, based on given observation it can be concluded that chemical reaction takes place when sodium is added to water.
A.Calcium and magnesium dissolve in water.
B.Calcium and magnesium evaporate on contact with the walls of the pipe.
C.Calcium and magnesium form precipitates of their respective oxides.
It's C, calcium and magnesium form precipitates of their respective oxide
The statement 'Calcium and magnesium form precipitates of their respective oxides' best describes the chemical change as it involves a reaction that transforms the calcium and magnesium into new compounds, their oxides, which can clog pipes.
The statement that best describes this change as a chemical change is C. Calcium and magnesium form precipitates of their respective oxides. This represents a chemical change because it involves a reaction that transforms the calcium and magnesium into new substances - their oxides. Here's how it works: in the presence of oxygen, calcium and magnesium in hard water can undergo an oxidation process. During this oxidation, the calcium becomes calcium oxide and the magnesium becomes magnesium oxide. These oxides are less soluble in water and form precipitates, which can accumulate and clog the pipes.
#SPJ6
Answer : The correct option is, (1) ions.
Explanation :
According to the Arrhenius concept, an acid is a type of substance which ionizes in water to gives ions (hydronium ions or hydrogen ions) and a base is a type of substance which ionizes in water to gives ions (hydroxide ions).
As we know that KOH is a base which ionizes in water to gives ions (hydroxide ions) and ions.
Hence, potassium hydroxide is classified as an Arrhenius base because KOH contains ions.
Answer:
Zinc doesn't react with water.
Explanation:
It forms a layer of insoluble zinc hydroxide.
2. It is the simplest ratio of atoms in a formula unit.
3. It represents the true molecular mass of a chemical formula.
4. It represents the highest ratio of coefficients in a chemical formula.
Answer:
2. It is the simplest ratio of atoms in a formula unit.
Explanation:
The empirical formula refers to how to provide the minimum proportion in which chemical elements combine into one substance. Sometimes it may happen that the minimum formula is equal to the molecular formula of the compound; However, this is not always true. In short, the empirical formula refers to the simplest ratio of atoms in a unit of formula.
For example, the empirical or minimal formula of water is H2O, indicating that there is a 2: 1 ratio between the elements that make up water molecules. And, coincidentally, this is also the molecular formula of water.
Answer:
164atm
Explanation:
Given parameters:
Initial pressure of tank = 150atm
Initial temperature of tank = 27°C = 27 + 273 = 300K
New temperature of tank = 55°C = 328K
Unknown:
New pressure of gas = ?
Solution:
From the combined gas law, at constant volume, the pressure of a given gas varies directly with the absolute temperature.
Mathematically;
=
P and T are pressure and temperature values
1 and 2 are the initial and new states
Insert the parameters and solve;
=
300P₂ = 150 x 328
P₂ = 164atm