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4 years ago

Calculate the molecular mass of Na2HPO4

Chemistry

1 answer:

seropon [69]4 years ago

5 0

Answer:

Molar mass of Na2HPO4=141.96, of Na2HPO4. 12H2O = 358.14: so to get the same 0.4 M: 28.65/358.14*141.96 g, add water until you reach 200ml , dissolve all solid and then filter to make sterile.

Explanation:

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A student places a 100.0°C piece of metal that weighs 85.5 g into 122 mL of 16.0°C water. If the final temperature is 20.2°C, wh

Musya8 [376]

Answer:

The specific heat of the metal is 0.314 J/g°C

Explanation:

Step 1: data given

Temperature of the piece of metal = 100.0 °C

Mass of the metal = 85.5 grams

Volume of water = 122 mL = 122 grams

Temperature of water = 16.0 °C

The final temperature of water = 20.2 °C

The specific heat of water = 4.184 J/g°C

Step 2: Calculate the specific heat of metal

Heat gained= heat lost

Qgained = - Qlost

Qwater = -Qmetal

Q = m*c* ΔT

m(metal)*c(metal)*ΔT(metal) = -m(water)*c(water)*ΔT(water)

⇒m(metal) = mass of metal = 85.5 grams

⇒c(metal) = the specific heat of metal = TO BE DETERMINED

⇒ΔT(metal) = the change of temperature of metal = T2 - T1 = 20.2 - 100 °C = -79.8 °C

⇒m(water) = the mass of water = 122 grams

⇒c(water) = the specific heat of water = 4.184 J/g°C

⇒ΔT(water) = the change of temperature of metal = T2 - T1 = 20.2 - 16.0 °C = 4.2 °C

85.5 *c(metal) * -79.8 = -122 * 4.184 * 4.2

c(metal) * (-6822.9) = -2143.9

c(metal) = 0.314 J/g°C

The specific heat of the metal is 0.314 J/g°C

7 0

3 years ago

1. Compare the masses and the charges for the three particles which make up the atom.

storchak [24]

Answer:

The charge on a neutron=1+-/neutral

It has a mass 1

The charge on electron is 1-/negative

It's mass is 1/1840

The charge on a proton is 1+

It has a mass 1 too.

Explanation:

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3 years ago

Tertiary or top consumers are animals at the top of the food web. They may feed off either primary or secondary consumers. What

babymother [125]

Answer:

Coyotes, Bald Eagles, & Gray wolf.

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3 years ago

Which statement about the density of warm water is most likely correct?

Damm [24]

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100 °C: 958.4 kg/m^360 °C: 983.2 kg/m^320 °C: 998.2 kg/m^3

Therefore, warm water has a lower density than water in colder temperature.

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3 years ago

What two molecules were condensed in an aldol condensation to produce (ch3)3cch=chcoch3?

inessss [21]

The given compound is being synthesized by condensing Acetone and Pivaldehyde (Trimethylacetaldehyde).

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4 years ago