Answer:
62.98 % of the sample of hydrate is water
Explanation:
Step 1: Data given
Mass of the sample of a hydrate of sodium carbonate (Na2CO3) = 2.026 grams
After heating, the mass of the sample is 0.750 g
Molar mass H2O = 18.02 g/mol
Step 2: Calculate mass of water
Mass water = mass of hydrate - mass of sample after heating
Mass water = 2.026 grams - 0.750 grams
Mass water = 1.276 grams
Step 3: Calculate mass % percent of water
Mass % of water = (mass of water / total mass hydrate) * 100 %
Mass % of water = (1.276 grams / 2.026 grams) *100 %
Mass % of water = 62.98 %
62.98 % of the sample of hydrate is water
Answer:
option A is correct ( sodium, calcium and barium)
Explanation:
Given compounds:
Sodium chloride , calcium sulfide, barium oxide
We know that metals form positive ions. In order to solve the problem we must identify the metals from given compounds.
Na⁺Cl⁻
Ca²⁺S²⁻
Ba²⁺O²⁻
We can see that sodium, calcium and barium contain positive charges.
Thus option A is correct.
Because sodium have one valance electron. When it combine with chlorine sodium lose its one electron to complete the octet and chlorine accept it to complete its octet. Thus sodium form positive ion and chlorine form negative ion.
Similarly barium and calcium are present in group 2. Both have two valance electron. When they lose them cation are formed.
Other option are incorrect because,
Option B have sulfur and oxygen which are anion.
Option C have chlorine which is also anion
Option D have chlorine, sulfur and oxygen that are anions.
fibrous roots; taproots
Explanation:
A taproot root consists of one large main root with smaller roots that branches off into the soil, while the fibrous roots consists of several main roots that branches off to form one mass of roots.
- The root system in plants helps them to absorb water and other nutrients from the soil.
- A taproot is much more like extension of stem that penetrates into the ground.
- It tapers at the end with many other smaller roots branching and networking from it.
- The fibrous root is a series of roots directly from the stem that independent of one another.
- Roots are used by plants for anchorage into the soil.
learn more:
Seedless vascular plants brainly.com/question/6047633
#learnwithBrainly
Answer;
K+ and NO3- ions
Explanation;
The main ions remaining are K+ and NO3- ions after pbi2 precipitation is complete.
However; There will always be tiny amounts of Pb2+ and I- ions, but most of them are in the solid precipitate.
