Ask question

Ask question

All categories

1 year ago

8

one ball rolls along a shelf at a steady rate. a second ball rolls off the shelf and gains speed as it falls in a curved path. w

hich must have an unbalanced force acting on it?

1 answer:

Salsk061 [2.6K]1 year ago

6 0

The ball that rolls at a steady rate

You might be interested in

0.01 M HCl solution has a pH of 2. Suppose that during the experiment, both the universal pH indicator and the cabbage indicator

NNADVOKAT [17]

It matches the universal pH indicator and is indicating the proper pH

5 0

2 years ago

Read 4 more answers

The density of liquid Z is 0.9237 g/mL. A student masses a cup

Ulleksa [173]

Answer:

37.65mL

Explanation:

Given parameters:

density of liquid Z = 0.9237g/mL

Mass of liquidZ + mass of cup = 50.7g

Mass of cup= 15.92g

Volume of liquid Z in cup=?

Solution:

Density is the mass per unit volume of a substance. It is mathematically expressed as shown below:

Density = $\frac{mass}{volume}$

To find the volume of liquid Z, we know the density of the liquid but we dont know the mass yet.

Mass of liquidZ = 50.7g - mass of cup = 50.7g - 15.92g = 34.98g

Therefore:

Volume of liquidZ = $\frac{mass of liquidZ}{density of liquidZ}$

= $\frac{34.98}{0.9237}$

= 37.65mL

3 0

1 year ago

The reaction between hydrogen gas and chlorine gas produces hydrogen chloride according to the following equation: H2(g) + Cl2(g

Andreyy89

Answer:

The enthalpy of reaction is -185 kJ

Explanation:

To get the reaction:

H₂(g) + Cl₂(g) → 2 HCl(g)

you must follow the following steps:

<em>1) Reactive molecules must break their bonds to obtain their atoms.</em>

H₂(g) → 2 H(g)

Cl₂(g) → 2 Cl(g)

Bond energy (or enthalpy) is the energy required to break one mole of bonds of a gaseous substance. In the case of diatomic molecules with a single bond, it corresponds to the energy necessary to dissociate 1 mole of said substance in the atoms that form it.

Whenever you want to break links you must supply energy, so the link enthalpy will have positive values; while when a mole of bonds is formed energy is released and the bond enthalpy of this process will be negative.

In this case you will then have:

H₂(g) → 2 H(g) ΔH=436 kJ/mol

Cl₂(g) → 2 Cl(g) ΔH=243 kJ/mol

So the total energy needed to break all the bonds is:

ΔH=1 mol*436 kJ/mol +1 mol* 243 kJ/mol= 679 kJ

2) The atoms that were obtained in the break of the bonds must be combined to obtain the product.

2 H (g) + 2 Cl (g) → 2 HCl (g)

Being the single bond energy for one mole of 431 kJ H-Cl bonds and considering that two moles of H-Cl bonds are formed, the ΔH is:

ΔH = -2 moles* (432 kJ/mol) = -864 kJ

As mentioned, when a mole of bonds is formed energy is released, the bond enthalpy of this process will be negative. So the formation of HCl is negative.

Hess's law states that the energy change in an overall chemical reaction is equal to the sum of the energy changes in the individual reactions comprising it. So:

ΔHtotal= -864 kJ + 679 kJ

ΔHtotal= -185 kJ

<u><em>The enthalpy of reaction is -185 kJ</em></u>

3 0

1 year ago

What mass of carbon dioxide could be made from 100 tonnes of calcium carbonate?

MA_775_DIABLO [31]

Total mass of CaCO3 = 40 amu of Ca + 12amu of C + 16×3 amu of oxygen = 100amu of CaCO3

i.e 100 tonnes of CaCO3 .

mass of CO2 = 12amu of C + 2× 16amu of O = 44 amu of CO2

mass % of CO2 in CaCO3 = (44/100)×100 =44%

i.e
44% of 100 tonnes is CO2.
=44 tonnes of CO2.

therefore, 44% of CO2 is present in CaCO3.

3 0

1 year ago

A quantity of 85.0 mL of 0.900 M HCl is mixed with 85.0 mL of 0.900 M KOH in a constantpressure calorimeter that has a heat capa

bogdanovich [222]

Explanation:

The given data is as follows.

$V_{1}$ = 85.0 ml, $M_{1}$ = 0.9 M

$V_{2}$ = 85.0 ml, $M_{1}$ = 0.9 M

Hence, number of moles of HCl and KOH will be the same because both the solutions have same volume and molarity.

So, No. of moles = Molarity × Volume

= $0.9 M \times 0.085 L$ (as 1 L = 1000 ml so, 85 ml = 0.085 L)

= 0.076 mol

As 1 mole gives 56.2 kJ/mol of heat of neutralization. Hence, calculate the heat of neutralization given by 0.076 moles as follows.

$56.2 kJ/mol \times 0.076 mol$

= 4.271 kJ

or, = 4271 J (as 1 kJ = 1000 J)

Therefore, heat released = - heat of gained by calorimeter

Since, it is given that density of the solution is similar to the density of water which is 1 g/ml.

Hence, mass of HCl = density × Volume of HCl

= 1.00 g/ml × 85.0 ml

= 85 g

Similarly, mass of KOH = = density × Volume of HCl

= 1.00 g/ml × 85.0 ml

= 85 g

Hence, total mass of the solution = 85 g + 85 g

= 170 g

Also, q = $mC \Delta T$

4271 J = $170 g \times 325 J/^{o}C \times (T_{f} - 18.24)^{o}C$

0.0773 = $T_{f} - 18.24$

$T_{f}$ = $18.317^{o}C$

Thus, we can conclude that final temperature of the mixed solution is $18.317^{o}C$ .

6 0

2 years ago